The document discusses drugs that act on the kidney to promote urine formation and regulate fluid and electrolyte balance. It describes the major processes involved in urine formation and the functions of the renal system. It then discusses different classes of diuretic drugs, including loop diuretics, thiazide diuretics, potassium-sparing diuretics, osmotic diuretics, vasopressin antagonists, and adenosine receptor antagonists. It explains their mechanisms of action, clinical uses, side effects, and drug interactions. Conditions like diuretic resistance are also mentioned.
This document provides information about antidiuretic drugs. It begins by defining antidiuretics as drugs that inhibit water excretion without affecting salt excretion. It then lists common antidiuretic drugs including antidiuretic hormone, desmopressin, thiazide diuretics, and others. The document discusses the mechanism of action of antidiuretic hormone, its effects on various organs like the kidneys and blood vessels, and conditions it can be used to treat like diabetes insipidus. It also covers antidiuretic hormone receptors, interactions with other drugs, and potential adverse effects.
This document discusses drugs that affect the gastrointestinal system. It covers topics including peptic ulcer disease, constipation, diarrhea, vomiting, and digestion. It describes factors that increase or decrease acidity in peptic ulcer disease. It then summarizes different drug classes used to treat peptic ulcers, constipation, diarrhea, vomiting, and digestive issues. These include H2 receptor antagonists, proton pump inhibitors, anticholinergics, prostaglandin analogs, antacids, antibiotics, laxatives, antidiarrheals, antiemetics, and digestion aids.
Diuretics act at different sites along the nephron to promote the excretion of sodium, chloride, and water. The main classes are carbonic anhydrase inhibitors, loop diuretics, thiazides, potassium-sparing diuretics, and osmotic diuretics. They are used to treat conditions like edema, hypertension, and liver cirrhosis. Each class has a distinct mechanism of action and side effect profile. For example, loop diuretics inhibit sodium reabsorption in the loop of Henle but can cause ototoxicity, while thiazides target the distal tubule and cause hypokalemia. The site and mechanism of the drug determines its clinical applications and adverse effects
This document discusses drugs used for congestive heart failure (CHF). It begins by defining heart failure as the heart's inability to pump enough blood to the body. It then classifies CHF drugs into those with positive inotropic effects, like cardiac glycosides and phosphodiesterase inhibitors, and those without, like diuretics and ACE inhibitors. The document provides detailed mechanisms of action, therapeutic uses, benefits, and adverse effects of various drug classes. It emphasizes that diuretics, ACE inhibitors, beta blockers, and spironolactone have been shown to reduce mortality and hospitalizations in CHF patients.
1. Diuretics are drugs that cause increased excretion of water and sodium in urine. They are classified based on their mechanism and efficacy as high ceiling loop diuretics, medium efficacy thiazides, weak carbonic anhydrase inhibitors, and potassium-sparing diuretics.
2. Loop diuretics like furosemide inhibit sodium reabsorption in the ascending loop of Henle. Thiazides like hydrochlorothiazide act in the distal convoluted tubule. Carbonic anhydrase inhibitors inhibit the enzyme carbonic anhydrase.
3. Diuretics are used to treat heart failure, liver cir
The document discusses drugs that act on the kidney to promote urine formation and regulate fluid and electrolyte balance. It describes the major processes involved in urine formation and the functions of the renal system. It then discusses different classes of diuretic drugs, including loop diuretics, thiazide diuretics, potassium-sparing diuretics, osmotic diuretics, vasopressin antagonists, and adenosine receptor antagonists. It explains their mechanisms of action, clinical uses, side effects, and drug interactions. Conditions like diuretic resistance are also mentioned.
This document provides information about antidiuretic drugs. It begins by defining antidiuretics as drugs that inhibit water excretion without affecting salt excretion. It then lists common antidiuretic drugs including antidiuretic hormone, desmopressin, thiazide diuretics, and others. The document discusses the mechanism of action of antidiuretic hormone, its effects on various organs like the kidneys and blood vessels, and conditions it can be used to treat like diabetes insipidus. It also covers antidiuretic hormone receptors, interactions with other drugs, and potential adverse effects.
This document discusses drugs that affect the gastrointestinal system. It covers topics including peptic ulcer disease, constipation, diarrhea, vomiting, and digestion. It describes factors that increase or decrease acidity in peptic ulcer disease. It then summarizes different drug classes used to treat peptic ulcers, constipation, diarrhea, vomiting, and digestive issues. These include H2 receptor antagonists, proton pump inhibitors, anticholinergics, prostaglandin analogs, antacids, antibiotics, laxatives, antidiarrheals, antiemetics, and digestion aids.
Diuretics act at different sites along the nephron to promote the excretion of sodium, chloride, and water. The main classes are carbonic anhydrase inhibitors, loop diuretics, thiazides, potassium-sparing diuretics, and osmotic diuretics. They are used to treat conditions like edema, hypertension, and liver cirrhosis. Each class has a distinct mechanism of action and side effect profile. For example, loop diuretics inhibit sodium reabsorption in the loop of Henle but can cause ototoxicity, while thiazides target the distal tubule and cause hypokalemia. The site and mechanism of the drug determines its clinical applications and adverse effects
This document discusses drugs used for congestive heart failure (CHF). It begins by defining heart failure as the heart's inability to pump enough blood to the body. It then classifies CHF drugs into those with positive inotropic effects, like cardiac glycosides and phosphodiesterase inhibitors, and those without, like diuretics and ACE inhibitors. The document provides detailed mechanisms of action, therapeutic uses, benefits, and adverse effects of various drug classes. It emphasizes that diuretics, ACE inhibitors, beta blockers, and spironolactone have been shown to reduce mortality and hospitalizations in CHF patients.
1. Diuretics are drugs that cause increased excretion of water and sodium in urine. They are classified based on their mechanism and efficacy as high ceiling loop diuretics, medium efficacy thiazides, weak carbonic anhydrase inhibitors, and potassium-sparing diuretics.
2. Loop diuretics like furosemide inhibit sodium reabsorption in the ascending loop of Henle. Thiazides like hydrochlorothiazide act in the distal convoluted tubule. Carbonic anhydrase inhibitors inhibit the enzyme carbonic anhydrase.
3. Diuretics are used to treat heart failure, liver cir
Cardiac glycosides like digoxin are used to treat heart failure and cardiac arrhythmias. They work by inhibiting sodium-potassium ATPase, increasing intracellular calcium levels, and enhancing cardiac contractility. Common side effects include nausea, arrhythmias, and toxicity at high levels. While they were once a standard treatment, newer heart failure drugs like ACE inhibitors, ARBs, beta blockers, and diuretics are now preferred due to their better safety profiles. Digitalis remains an option when symptoms are not adequately controlled by other treatments.
Peptic ulcers are caused by a loss of gastric or duodenal mucosa leading to ulcer formation. Drugs used to treat peptic ulcers work by reducing acid secretion, neutralizing acid, protecting the ulcer, or eradicating Helicobacter pylori infection. Common classes of drugs include H2 receptor antagonists, proton pump inhibitors, antacids, sucralfate, bismuth subcitrate, and multi-drug regimens for H. pylori. The document provides details on the mechanisms, uses, and side effects of these various drug classes.
This document discusses drugs used for treating shock. It describes different types of shock including hypovolemic, septic, cardiogenic, and anaphylactic shock. It then discusses three categories of drugs used to treat shock: vasoconstrictors like epinephrine and norepinephrine which increase blood pressure, cardio tonic drugs like digoxin, dobutamine, and dopamine which increase heart function, and fluid replacement agents like blood, colloids, and crystalloids which replace lost fluids. Epinephrine causes vasoconstriction, increases heart rate and output, and dilates airways. Norepinephrine also causes vasoconstriction. Digoxin increases heart contraction force while
This document discusses various classes of drugs acting on the cardiovascular system including cardiotonic drugs, antihypertensive drugs, antiarrhythmic drugs, and antianginal drugs. It provides details on mechanisms of action, indications, and side effects of specific drugs in these classes such as digitalis, alpha-methyl dopa, clonidine, calcium channel blockers, ACE inhibitors, and angiotensin receptor blockers. The document aims to comprehensively cover the pharmacology of commonly used cardiovascular drugs through detailed explanations of their properties and effects.
Hematinics such as iron, vitamin B12, folic acid, and erythropoietin are used to treat various types of anemia. Iron deficiency, vitamin B12 or B9 deficiency, blood loss, and bone marrow disorders can all cause anemia by disrupting the balance of red blood cell production and destruction. Oral iron supplements are usually the first treatment for iron-deficiency anemia, while vitamin B12 and B9 deficiencies may be treated with supplements or injections depending on severity. Erythropoietin injections can help stimulate red blood cell production in conditions like chronic kidney disease or cancer chemotherapy-induced anemia.
1) Diuretics are drugs that cause net loss of sodium and water in urine. They are classified as loop diuretics, thiazide diuretics, potassium-sparing diuretics, carbonic anhydrase inhibitors, and osmotic diuretics.
2) Loop diuretics like furosemide work by inhibiting sodium-potassium-chloride reabsorption in the loop of Henle, while thiazide diuretics inhibit sodium-chloride reabsorption in the distal tubule.
3) Diuretics are used to treat conditions like edema, hypertension, heart failure, nephrotic syndrome, and cerebral edema. Common side effects include
This document provides information on the pharmacology of diuretics. It begins by explaining that diuretics cause a net loss of sodium and water in urine but sodium balance is restored through homeostatic mechanisms. It then classifies diuretics and describes various classes in detail, including their mechanisms and sites of action, uses, and adverse effects. The classes discussed include high efficacy loop diuretics like furosemide, medium efficacy thiazides, weak carbonic anhydrase inhibitors, potassium sparing aldosterone antagonists, and renal sodium channel inhibitors.
Thiazide diuretics act in the distal convoluted tubule to inhibit sodium reabsorption and promote excretion of sodium, chloride, and water. They are commonly used to treat hypertension and heart failure by reducing extracellular volume. Common thiazide diuretics include hydrochlorothiazide, chlorthalidone, and bendroflumethiazide. Adverse effects include hypokalemia, hyponatremia, hyperglycemia and drug interactions that can be enhanced by their effects on fluid and electrolyte balance. Thiazides must be used cautiously in conditions like pregnancy, diabetes, and renal impairment.
Loop diuretics work by selectively inhibiting sodium chloride reabsorption in the thick ascending limb of Henle's loop. This makes them highly effective diuretic agents. They are rapidly absorbed and eliminated by the kidneys. Common loop diuretics include furosemide, bumetanide, and torsemide. Loop diuretics are used to treat conditions causing edema such as heart failure, as well as hyperkalemia and acute renal failure. Potential side effects include hypokalemia, ototoxicity, and hypomagnesemia with prolonged use.
Diarrhea is a major cause of morbidity and mortality in developing countries. The mainstay of treatment is to correct fluid and electrolyte imbalance through oral rehydration therapy or IV fluids. Specific treatment depends on the cause and includes antimicrobial agents for infectious diarrhea and anti-motility drugs for non-infectious diarrhea. Anti-motility drugs like loperamide work by increasing intestinal transit time through mu and delta opioid receptors while anticholinergics decrease bowel motility and secretion. Antimicrobials are useful for specific infections while anti-inflammatory drugs are used for conditions like ulcerative colitis.
The document discusses expectorants and antitussives. It defines expectorants as drugs that increase bronchial secretion or reduce viscosity, facilitating removal by coughing. Only guaiphenesin is approved as an expectorant in the U.S. Expectorants are classified as bronchial secretion enhancers or mucolytics. Antitussives act in the CNS to suppress cough or act peripherally in the respiratory tract. Antitussives are classified as opioids, nonopioids, antihistamines, or peripherally acting drugs. The document provides examples and doses of expectorants and antitussives and discusses some combination antitussive-expectorant formulations.
This document discusses various haematinics including iron, vitamin B12, folic acid, and erythropoietin. It covers their roles in red blood cell formation, daily requirements, dietary sources, absorption and transport, deficiency states, preparations used to treat deficiencies, and therapeutic uses to treat conditions like iron deficiency anemia and megaloblastic anemia. It provides details on the pharmacokinetics and pharmacology of administering these substances.
Brief descriptions of adrenergic drugs with individual agents with classification, therapeutic uses with dose, mechanism of action, adverse events, contraindications etc. Adrenergic drugs are drugs with actions similar to that of adrenaline (epinephrine) or of sympathetic stimulation.
This document discusses the adrenergic system including adrenergic receptors, location and functions of different receptor types, adrenergic drugs, and pharmacological actions. It also covers adrenergic receptor antagonists including classifications of alpha-blockers and beta-blockers, their uses and adverse effects. The key points are: there are alpha and beta adrenergic receptors which are located in various organs and tissues and have different functions; common adrenergic drugs act as pressor agents, bronchodilators or cardiac stimulants; and adrenergic receptor antagonists like alpha-blockers and beta-blockers are used to treat conditions like hypertension, angina, heart failure and gl
This document provides an overview of asthma, including its definition, characteristics, classification, pathophysiology, symptoms, diagnosis, treatment approaches, and medications. Asthma is defined as a chronic inflammatory airway disorder characterized by bronchial hyperresponsiveness and reversible airway obstruction. It is classified as extrinsic, intrinsic, or mixed. Diagnosis involves assessing history, symptoms, and lung function tests. Treatment follows a stepwise approach starting with short-acting bronchodilators and inhaled corticosteroids, adding additional controllers as needed. Status asthmaticus refers to an acute, severe exacerbation unresponsive to usual treatment.
short and simple study on the topic of laxative and purgatives which is very usefull for the student , teachers, as well as health cares peoples. this study is done by the student with the help of teachers
This document discusses the pharmacotherapy of peptic ulcers. It begins by classifying the main drugs used: 1) those that inhibit gastric acid secretion like H2 blockers and proton pump inhibitors, 2) antacids that neutralize acid, 3) ulcer protectives like sucralfate, and 4) anti-H. pylori drugs for eradication. It then goes into detail about the mechanisms, uses, and side effects of the major drug classes. H2 blockers competitively block H2 receptors to suppress acid secretion. Proton pump inhibitors irreversibly inactivate the H+/K+ ATPase pump for prolonged acid inhibition. Antacids chemically neutralize acid. Sucralfate
Anticholinergic drugs work by blocking the actions of acetylcholine in the parasympathetic nervous system. They are competitive antagonists that bind to muscarinic receptors, reversibly blocking acetylcholine transmission. Atropine is a prototypical anticholinergic derived from deadly nightshade. It causes dilation of the pupils, increased heart rate, decreased secretions, and relaxed smooth muscles. Anticholinergics are used to treat Parkinson's disease, motion sickness, asthma, peptic ulcers, overactive bladder, and other conditions. Side effects include dry mouth, blurred vision, constipation, urinary retention, and excitement or delirium in overdose.
Constipation is a common complaint defined as infrequent bowel movements and difficult bowel movements. The Rome III criteria are used to diagnose chronic constipation. Constipation can be primary/functional with no clear cause or secondary due to causes like immobility, diet, medical conditions, or medications. Management involves lifestyle changes and laxatives. Laxatives are classified as bulk forming, stool softeners, stimulant purgatives, or osmotic purgatives. Bulk forming laxatives like bran and psyllium work by increasing stool bulk while osmotic laxatives like lactulose work by retaining fluid in the intestines. Diarrhea is defined as 3 or more loose stools per day and can
in this presentation i have tried to briefly discuss about diuretics (water pills), their classification, mechanism of action, pharmacokinetics and pharmacodynamics of these drugs
Cardiac glycosides like digoxin are used to treat heart failure and cardiac arrhythmias. They work by inhibiting sodium-potassium ATPase, increasing intracellular calcium levels, and enhancing cardiac contractility. Common side effects include nausea, arrhythmias, and toxicity at high levels. While they were once a standard treatment, newer heart failure drugs like ACE inhibitors, ARBs, beta blockers, and diuretics are now preferred due to their better safety profiles. Digitalis remains an option when symptoms are not adequately controlled by other treatments.
Peptic ulcers are caused by a loss of gastric or duodenal mucosa leading to ulcer formation. Drugs used to treat peptic ulcers work by reducing acid secretion, neutralizing acid, protecting the ulcer, or eradicating Helicobacter pylori infection. Common classes of drugs include H2 receptor antagonists, proton pump inhibitors, antacids, sucralfate, bismuth subcitrate, and multi-drug regimens for H. pylori. The document provides details on the mechanisms, uses, and side effects of these various drug classes.
This document discusses drugs used for treating shock. It describes different types of shock including hypovolemic, septic, cardiogenic, and anaphylactic shock. It then discusses three categories of drugs used to treat shock: vasoconstrictors like epinephrine and norepinephrine which increase blood pressure, cardio tonic drugs like digoxin, dobutamine, and dopamine which increase heart function, and fluid replacement agents like blood, colloids, and crystalloids which replace lost fluids. Epinephrine causes vasoconstriction, increases heart rate and output, and dilates airways. Norepinephrine also causes vasoconstriction. Digoxin increases heart contraction force while
This document discusses various classes of drugs acting on the cardiovascular system including cardiotonic drugs, antihypertensive drugs, antiarrhythmic drugs, and antianginal drugs. It provides details on mechanisms of action, indications, and side effects of specific drugs in these classes such as digitalis, alpha-methyl dopa, clonidine, calcium channel blockers, ACE inhibitors, and angiotensin receptor blockers. The document aims to comprehensively cover the pharmacology of commonly used cardiovascular drugs through detailed explanations of their properties and effects.
Hematinics such as iron, vitamin B12, folic acid, and erythropoietin are used to treat various types of anemia. Iron deficiency, vitamin B12 or B9 deficiency, blood loss, and bone marrow disorders can all cause anemia by disrupting the balance of red blood cell production and destruction. Oral iron supplements are usually the first treatment for iron-deficiency anemia, while vitamin B12 and B9 deficiencies may be treated with supplements or injections depending on severity. Erythropoietin injections can help stimulate red blood cell production in conditions like chronic kidney disease or cancer chemotherapy-induced anemia.
1) Diuretics are drugs that cause net loss of sodium and water in urine. They are classified as loop diuretics, thiazide diuretics, potassium-sparing diuretics, carbonic anhydrase inhibitors, and osmotic diuretics.
2) Loop diuretics like furosemide work by inhibiting sodium-potassium-chloride reabsorption in the loop of Henle, while thiazide diuretics inhibit sodium-chloride reabsorption in the distal tubule.
3) Diuretics are used to treat conditions like edema, hypertension, heart failure, nephrotic syndrome, and cerebral edema. Common side effects include
This document provides information on the pharmacology of diuretics. It begins by explaining that diuretics cause a net loss of sodium and water in urine but sodium balance is restored through homeostatic mechanisms. It then classifies diuretics and describes various classes in detail, including their mechanisms and sites of action, uses, and adverse effects. The classes discussed include high efficacy loop diuretics like furosemide, medium efficacy thiazides, weak carbonic anhydrase inhibitors, potassium sparing aldosterone antagonists, and renal sodium channel inhibitors.
Thiazide diuretics act in the distal convoluted tubule to inhibit sodium reabsorption and promote excretion of sodium, chloride, and water. They are commonly used to treat hypertension and heart failure by reducing extracellular volume. Common thiazide diuretics include hydrochlorothiazide, chlorthalidone, and bendroflumethiazide. Adverse effects include hypokalemia, hyponatremia, hyperglycemia and drug interactions that can be enhanced by their effects on fluid and electrolyte balance. Thiazides must be used cautiously in conditions like pregnancy, diabetes, and renal impairment.
Loop diuretics work by selectively inhibiting sodium chloride reabsorption in the thick ascending limb of Henle's loop. This makes them highly effective diuretic agents. They are rapidly absorbed and eliminated by the kidneys. Common loop diuretics include furosemide, bumetanide, and torsemide. Loop diuretics are used to treat conditions causing edema such as heart failure, as well as hyperkalemia and acute renal failure. Potential side effects include hypokalemia, ototoxicity, and hypomagnesemia with prolonged use.
Diarrhea is a major cause of morbidity and mortality in developing countries. The mainstay of treatment is to correct fluid and electrolyte imbalance through oral rehydration therapy or IV fluids. Specific treatment depends on the cause and includes antimicrobial agents for infectious diarrhea and anti-motility drugs for non-infectious diarrhea. Anti-motility drugs like loperamide work by increasing intestinal transit time through mu and delta opioid receptors while anticholinergics decrease bowel motility and secretion. Antimicrobials are useful for specific infections while anti-inflammatory drugs are used for conditions like ulcerative colitis.
The document discusses expectorants and antitussives. It defines expectorants as drugs that increase bronchial secretion or reduce viscosity, facilitating removal by coughing. Only guaiphenesin is approved as an expectorant in the U.S. Expectorants are classified as bronchial secretion enhancers or mucolytics. Antitussives act in the CNS to suppress cough or act peripherally in the respiratory tract. Antitussives are classified as opioids, nonopioids, antihistamines, or peripherally acting drugs. The document provides examples and doses of expectorants and antitussives and discusses some combination antitussive-expectorant formulations.
This document discusses various haematinics including iron, vitamin B12, folic acid, and erythropoietin. It covers their roles in red blood cell formation, daily requirements, dietary sources, absorption and transport, deficiency states, preparations used to treat deficiencies, and therapeutic uses to treat conditions like iron deficiency anemia and megaloblastic anemia. It provides details on the pharmacokinetics and pharmacology of administering these substances.
Brief descriptions of adrenergic drugs with individual agents with classification, therapeutic uses with dose, mechanism of action, adverse events, contraindications etc. Adrenergic drugs are drugs with actions similar to that of adrenaline (epinephrine) or of sympathetic stimulation.
This document discusses the adrenergic system including adrenergic receptors, location and functions of different receptor types, adrenergic drugs, and pharmacological actions. It also covers adrenergic receptor antagonists including classifications of alpha-blockers and beta-blockers, their uses and adverse effects. The key points are: there are alpha and beta adrenergic receptors which are located in various organs and tissues and have different functions; common adrenergic drugs act as pressor agents, bronchodilators or cardiac stimulants; and adrenergic receptor antagonists like alpha-blockers and beta-blockers are used to treat conditions like hypertension, angina, heart failure and gl
This document provides an overview of asthma, including its definition, characteristics, classification, pathophysiology, symptoms, diagnosis, treatment approaches, and medications. Asthma is defined as a chronic inflammatory airway disorder characterized by bronchial hyperresponsiveness and reversible airway obstruction. It is classified as extrinsic, intrinsic, or mixed. Diagnosis involves assessing history, symptoms, and lung function tests. Treatment follows a stepwise approach starting with short-acting bronchodilators and inhaled corticosteroids, adding additional controllers as needed. Status asthmaticus refers to an acute, severe exacerbation unresponsive to usual treatment.
short and simple study on the topic of laxative and purgatives which is very usefull for the student , teachers, as well as health cares peoples. this study is done by the student with the help of teachers
This document discusses the pharmacotherapy of peptic ulcers. It begins by classifying the main drugs used: 1) those that inhibit gastric acid secretion like H2 blockers and proton pump inhibitors, 2) antacids that neutralize acid, 3) ulcer protectives like sucralfate, and 4) anti-H. pylori drugs for eradication. It then goes into detail about the mechanisms, uses, and side effects of the major drug classes. H2 blockers competitively block H2 receptors to suppress acid secretion. Proton pump inhibitors irreversibly inactivate the H+/K+ ATPase pump for prolonged acid inhibition. Antacids chemically neutralize acid. Sucralfate
Anticholinergic drugs work by blocking the actions of acetylcholine in the parasympathetic nervous system. They are competitive antagonists that bind to muscarinic receptors, reversibly blocking acetylcholine transmission. Atropine is a prototypical anticholinergic derived from deadly nightshade. It causes dilation of the pupils, increased heart rate, decreased secretions, and relaxed smooth muscles. Anticholinergics are used to treat Parkinson's disease, motion sickness, asthma, peptic ulcers, overactive bladder, and other conditions. Side effects include dry mouth, blurred vision, constipation, urinary retention, and excitement or delirium in overdose.
Constipation is a common complaint defined as infrequent bowel movements and difficult bowel movements. The Rome III criteria are used to diagnose chronic constipation. Constipation can be primary/functional with no clear cause or secondary due to causes like immobility, diet, medical conditions, or medications. Management involves lifestyle changes and laxatives. Laxatives are classified as bulk forming, stool softeners, stimulant purgatives, or osmotic purgatives. Bulk forming laxatives like bran and psyllium work by increasing stool bulk while osmotic laxatives like lactulose work by retaining fluid in the intestines. Diarrhea is defined as 3 or more loose stools per day and can
in this presentation i have tried to briefly discuss about diuretics (water pills), their classification, mechanism of action, pharmacokinetics and pharmacodynamics of these drugs
Diuretics and antidiuretics detail STUDYNittalVekaria
diuretics and antidiuretics detail study
-diuretic are the drug which increase the urine formation and excretion.
- antidiuretic work by decrease the urine formation.
classification, mechanism of action, use ,pharmacokinetic, pharmacodynamic,adverse effect
-newer drug
-banned diuretic and antidiuretic drug
This document discusses different classes of diuretic drugs, including their sites of action in the nephron, mechanisms of action, therapeutic uses, and side effects. It covers osmotic diuretics, carbonic anhydrase inhibitors, thiazide diuretics, loop diuretics, and potassium-sparing diuretics. The main points are that diuretics work by inhibiting transport in different parts of the nephron like the proximal tubule, loop of Henle, or distal convoluted tubule. They are used to treat conditions like edema, hypertension, and heart failure. Common side effects among the classes include electrolyte imbalances and metabolic alterations.
Diuretics are drugs that promote the excretion of sodium and water from the body by acting on the kidney. They work by interfering with sodium transport mechanisms in different segments of the nephron. The main types are loop diuretics which act on the thick ascending limb of the loop of Henle, thiazide diuretics which act on the early distal tubule, and potassium-sparing diuretics which act on the late distal tubule and collecting duct. Diuretics are important drugs used to treat hypertension, heart failure, and edema.
The document discusses the mechanisms and effects of different classes of diuretic drugs, including thiazide and loop diuretics. It explains that thiazides act in the distal tubule to inhibit sodium reabsorption, causing a modest diuresis. Loop diuretics act in the ascending loop of Henle and cause a greater natriuresis than thiazides. Both can cause hypokalemia and other electrolyte abnormalities as side effects. The document outlines the clinical uses of these diuretics to treat conditions like edema, hypertension, and hypocalciuria. It also discusses factors that can contribute to diuretic resistance.
This document provides information on diuretic drugs, including their mechanisms and sites of action, indications for use, and adverse effects. It discusses loop diuretics like furosemide and bumetanide that act in the thick ascending loop of Henle, thiazide diuretics like hydrochlorothiazide that act in the distal tubule, and potassium-sparing diuretics like amiloride and spironolactone that act in the collecting ducts. It also covers carbonic anhydrase inhibitors and osmotic diuretics. Non-diuretic uses and combinations with other drugs are mentioned. Resistance, interactions, and specific adverse effects are summarized for each drug class.
1. Thiazide and loop diuretics act at different sites along the nephron to inhibit sodium reabsorption and cause increased sodium and water excretion.
2. They are used to treat edema, hypertension, and other conditions. Common side effects include hypokalemia, hypomagnesemia, and metabolic alterations.
3. The effects, pharmacokinetics, clinical uses and adverse effects of thiazide and loop diuretics are described and compared in detail. Combination diuretic therapy and managing diuretic resistance are also discussed.
This document discusses different classes of diuretic medications, their mechanisms of action, indications, and side effects. It describes:
1) Loop diuretics which inhibit sodium reabsorption in the loop of Henle, causing increased excretion of sodium, chloride, and water. Their main indications include heart failure and edema.
2) Thiazide diuretics which inhibit sodium reabsorption in the distal convoluted tubule. They are used to treat hypertension and have fewer side effects than loop diuretics.
3) Carbonic anhydrase inhibitors which inhibit bicarbonate reabsorption in the proximal tubule, causing a metabolic acidosis. Their main use is for glaucoma.
This ppt tells us about the topics diuretics and antidiuretics.
It also indicates us about their classification, mechanism of action, side effects and many more.
This document discusses diuretics, with a special focus on hydrochlorothiazide. It provides details on renal physiology and pharmacology. It describes the main types of diuretics and their mechanisms of action. It discusses thiazide diuretics in depth, including common examples like hydrochlorothiazide, their effects, kinetics, side effects, and clinical uses, especially for hypertension.
The document summarizes renal physiology and kidney function. It discusses:
1) The structure of the kidney including nephrons, collecting ducts, and microvasculature. Nephron number is established prenatally and cannot be replaced if lost.
2) Urine formation through selective retention and elimination of solutes and water by different nephron segments including the glomerulus, proximal tubule, loop of Henle, and collecting ducts.
3) Causes, types (prerenal, intrarenal, postrenal), phases, prevention and management of acute renal failure and end-stage renal disease where dialysis or transplantation is needed for survival.
This document provides an overview of diuretics, including their definition, classification, mechanisms of action, and pharmacology. It focuses on the physiology of urine formation and the mechanisms and sites of action of thiazide and loop diuretics. Thiazide diuretics act in the early distal tubule by inhibiting sodium-chloride reabsorption, while loop diuretics act in the thick ascending limb of the loop of Henle by blocking the sodium-potassium-chloride transporter. The document compares the mechanisms, indications, doses, side effects and drug interactions of thiazide and loop diuretics.
The document discusses kidney function and urine formation processes. It then summarizes the key functions of the kidneys, which include regulating electrolyte and fluid balance and removing waste from the blood. It describes the three main processes involved in urine formation - filtration, reabsorption, and secretion. The document then focuses on hypertension, describing classifications of blood pressure and types of hypertension. It outlines mechanisms for blood pressure control and discusses non-pharmacological and pharmacological approaches to hypertension management.
This document provides an overview of diuretics, including their definition, classification, mechanisms of action, and side effects. It discusses the physiology of urine formation and the roles of the kidney in homeostasis. Specific sections cover thiazide diuretics, loop diuretics, their mechanisms in inhibiting sodium reabsorption in the distal tubule and thick ascending limb, respectively. Adverse effects include hypokalemia, hyperuricemia, and effects on calcium and magnesium levels. The document compares the potencies and durations of action of different diuretic classes and individual drugs.
This a is a slide set (42 slides) covering clinically used drugs for lipid lowering. This is an updated version of the lecture series for the 2021-2022 academic year. Suitable for intermediate level learners
The document announces a virtual conference on June 30th, 2021 hosted by the IUPHAR Education Section to discuss future-proofing pharmacology education. The conference consists of two sessions:
Session 1 from 9:00-10:30 am UTC will feature a keynote by Professor Ray Land on transformational approaches to pharmacology education, followed by Q&A on prerecorded presentations on student-led pharmacology research and transforming pharmacology practicals for blended learning.
Session 2 from 21:00-22:30 pm UTC will include a workshop on core concepts and concept inventories led by Professor Paul White, followed by Q&A on prerecorded presentations about coming together as a society to future
The document announces an IUPHAR virtual conference on June 30th, 2021 about future-proofing pharmacology education. The conference consists of two sessions.
Session 1 runs from 9-10:30 am UTC and features a keynote by Professor Ray Land on threshold concepts and troublesome knowledge in pharmacology education. It also includes prerecorded presentations on student-led pharmacology research, transforming pharmacology practicals for blended learning, incorporating gamification to engage learners, and the IUPHAR Pharmacology Education Project.
Session 2 runs from 9-10:30 pm UTC and includes a workshop on core concepts and concept inventories led by Professor Paul White. It also features prerecorded presentations on
40 slides that focus on the drugs used to treat epilepsy (anti-epileptic drugs) and their their primary molecular mechanisms of action. Produced by Stephen Kelley (University of Dundee, UK).
This document provides an overview of epilepsy pharmacotherapy, including classification of seizures and epilepsy. It discusses the pathophysiology and causes of epilepsy, classification of seizure types, management strategies, first aid for seizures, and considerations for pregnancy. Key points covered include the definition of seizures and epilepsy, that up to 1/3 of cases are idiopathic while others are symptomatic, classification of focal and generalized seizures, and first-line treatment involving antiepileptic drugs.
A teaching slide set describing the mechanisms of action and clinical use of local anaesthetics. This session is a basic introduction to the pharmacodynamics and pharmacokinetics of local anaesthetics. It is aimed at preclinical medical or dental students, or students in the early years of a pharmacology degree.
This 11-slide slide set created with PowerPoint describes the organic nitrates and their use in the treatment of angina pectoris. Contributed by Christopher Fowler, Umeå University, Sweden.
This set of 17 slides introduces students to the some of the basic physiological processes that are the targets of many analgesic drug classes. It is suitable for beginner/intermediate level learners.
This slide set provides an introduction at new learner to intermediate level to some of the most common drugs that are used clinically to modulate the rate and force of contraction of the heart. Created by Prof. JA Peters, University of Dundee School of Medicine.
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ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
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Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
Your Skill Boost Masterclass: Strategies for Effective Upskilling
Drugs acting on the kidney lectures 1 and 2
1. Drugs Acting on the Kidney (1 and 2)
Professor John Peters
E-mail j.a.peters@dundee.ac.uk
2. Learning Objectives
Following this lecture, students should be able to:
Recall the range of drugs that act upon the kidney
Identify the major sites of diuretic action in the nephron
Describe in detail the mechanism of action of the loop diuretics
List the clinical uses and main adverse effects of the loop diuretics
Describe in detail the mechanism of action of the thiazide diuretics
List the clinical uses and main adverse effects of the thiazide diuretics
Explain why loop and thiazide diuretics cause hypokalaemia
Describe the mechanisms of action of the potassium sparing diuretics
noting the distinct modes of action of aldosterone antagonists and
blockers of the epithelial sodium channel, ENaC
Describe the clinical uses of the potassium sparing diuretics and their
adverse effects
Recommended Reading
Rang and Dale’s Pharmacology (7th. Ed.) Chapter 28
3. Drugs Acting on the Kidney
Drugs acting on the kidney include
Diuretics are the most commonly used agents that:
increase urine flow, normally by inhibiting the reabsorption of
electrolytes (mainly sodium salts) at various sites in the nephron
Diuretics
Vasopressin (antidiuretic hormone; ADH) receptor agonists and
antagonists
Uricosuric drugs (agents promoting excretion of uric acid into the
urine)
are used to enhance excretion of salt and water in conditions where
an increase in the volume of interstitial fluid (i.e. oedema) causes
tissue swelling
Inhibitors of sodium-glucose co-transporter 2 (SGLT2)
Those used in renal failure
Those that alter the pH of the urine
4. Formation of interstitial fluid is proportional to: (Pc – Pi) – (p - i)
Disease states that increase Pc or decrease p and produce
oedema include:
• the nephrotic syndrome
Oedema
results from an imbalance between the rate of formation and
absorption of interstitial fluid
Pc p
Pi i
Capillary
Interstitial fluid
• hepatic cirrhosis with ascites
• congestive heart failure
5. Diseases Associated With Oedema Responding to Diuretic
Drug Therapy
The Nephrotic Syndrome
Involves a disorder of glomerular filtration, allowing protein
(largely albumin) to appear in the filtrate (proteinuria)
Decreased p
formation of
interstitial fluid
blood volume
cardiac output
Oedema
Activation of the
RAAS
Na+ and H20
retention
Pc, p
6. Congestive Heart Failure
Arises from reduced cardiac
output. Subsequent renal
hypoperfusion activates the renin-
angiotensin system
Expansion of blood volume
contributes to increased venous
and capillary pressures which,
combined with reduced p, causes
pulmonary and peripheral oedema
Hepatic Cirrhosis With Ascites
Increased pressure in the hepatic
portal vein, combined with decreased
production of albumin, causes loss of
fluid into the peritoneal cavity and
oedema (ascites)
Activation of the renin-angiotensin
system occurs in response to
decreased circulating volume
Oedema fluid mobilization by
diuretics. Note that collapse and
danger of thrombosis only occur
if massive use of diuretics is
employed). From Lüllmann et al.
(2000) Color Atlas of
Pharmacology
7. Sodium Reabsorption and the Major Sites of Diuretic
Action in the Nephron
Proximal convoluted tubule
1. Na+ (passive Cl- absorption)
2. Na+/H+ exchange (blocked by
carbonic anhydrase inhibitors)
Thick ascending limb of the loop of Henle
3. Na+/K+/2Cl- co-transport (blocked
by loop diuretics)
Distal convoluted tubule
4. Na+/H+ exchange (blocked by
carbonic anhydrase inhibitors)
5. Na+/Cl- co-transport (blocked by
thiazide diuretics)
Collecting tubule
6. Na+/K+ exchange (blocked by
potassium-sparing diuretics)
1
2
3
4
5
6
8. Diuretics – General Aspects
A very large proportion of NaCl and H2O that passes into the filtrate
via the glomerulus is reabsorbed – hence even a small inhibition of
reuptake can cause a marked increase in Na+ excretion
The site of action of many diuretics (thiazides, loop agents, potassium
sparing) is the apical membrane of tubular cells hence, if hydrophilic,
they must enter the filtrate to access that site
Entry to the filtrate is by either:
glomerular filtration (for drug not bound to plasma protein)
secretion via transport process in the proximal tubule
two transport systems are important
The organic anion transporters (OATs) – transport acidic drugs (e.g.
thiazides and loop agents)
The organic cation transporters (OCTs) – transport basic drugs (e.g.
triamterene and amiloride)
Secretion results in the concentration of diuretic in the filtrate being higher
than that in blood, contributing to pharmacological selectivity
9. Secretion of Diuretics in the Proximal Tubule
Organic anion transporters (OATs)
At the basolateral membrane organic
anions (OA-) enter cell by either diffusion,
or in exchange for α-ketoglutarate (α-KG)
via OATs
α-KG is transported into cell (against a
concentration gradient) via a Na+-
dicarboxylate transporter
At the apical membrane, OA- enters the
lumen via either multidrug resistance
protein 2 (MRP2), or OAT4 (in exchange
for α-KG)
Organic cation transporters (OCTs)
At the basolateral membrane organic
cations (OC+) enter the cell either by
diffusion, or OCT, (both driven by
negative potential of cell interior and
against a concentration gradient)
At the apical membrane, OC+ enters the
lumen via either multidrug resistance
protein 1 (MRP1), or OC+/H+ antiporters
(OCTN)
10. Mechanism of Action of Loop Diuretics
Na+
Na+
Na+
K+K+
K+ K+
Cl-2Cl- Cl-
Zona occludens
+ve -ve4-10 mV
Lumen Interstitium
Mg2+
Ca2+
Mg2+
Ca2+
Loop
diuretics
block
Maintainhightonicity
ofthemedulla
Tubular epithelium
of the TAL
Triple transporter
(Na+/K+/2Cl- co-
transporter; NKCC2)
K+/Cl- co-transporter
Na+/K+ ATPase
Key
K channel (ROMK)
Cl channel
TAL = thick
ascending limb of
the loop of Henlé
11. Pharmacodynamics
Inhibit the Na+/K+/2Cl- carrier by binding to the Cl- site and thus:
Loop Diuretics (1)
Principal drugs: Furosemide and Bumetanide
Possess an additional, indirect, venodilator action (before diuresis)
that is beneficial in pulmonary oedema caused by heart failure–
possibly results from: 1) increased formation of vasodilating
prostaglandins; 2) decreased responsiveness to angiotensin II and
noradrenaline; 3) opening of K+ channels in resistance vessels
Increase the load of Na+ delivered to distal regions of the nephron
(causing K+ loss)
Decrease the tonicity of the interstitium of the medulla
Prevent dilution of the filtrate in the thick ascending limb
Increase excretion of Ca2+ and Mg2+
Are ‘high ceiling’ agents causing 15-25% of filtered load of Na+ to
be excreted – rapid onset following i.v. administration
12. Loop Diuretics (2)
To treat hypertension (in patients resistant to other diuretics or anti-
hypertensive drugs - usually in the presence of renal insufficiency)
To reduce acutely elevated calcium levels in the serum
(hypercalcaemia) - note paracellular pathway in the thick
ascending limb of the loop of Henle
To increase urine volume in acute kidney failure
Clinical indications
To reduce salt and water overload associated with:
Acute pulmonary oedema (i.v.) Chronic heart failure
Chronic kidney failure Nephrotic syndrome
Hepatic cirrhosis with ascites
Pharmacokinetics
Well absorbed from the G.I. tract
Strongly bound to plasma protein
Enter nephron by the organic anion transport mechanism
13. Loop Diuretics (3)
Potassium loss producing low serum potassium levels
(hypokalaemia) – corrected by the concomitant use of potassium
sparing diuretics or potassium supplements
(note increases toxicity of digoxin and Class III antidysrhythmic drugs)
Increased plasma uric acid (hyperuricaemia) – partially
explained by competition between uric acid and loop agents
for the organic acid secretory mechanism in the proximal
tubule
Depletion of calcium and magnesium (paracellular pathway)
Decreased volume of circulating fluid (hypovolaemia) and
hypotension (particularly in the elderly)
Shift in acid-base towards alkaline side (metabolic alkalosis) –
caused by increased H+ secretion from intercalated cells in
collecting tubule
Adverse effects
14. Mechanism of Action of Thiazide Diuretics
Na+
Na+
Na+
+
K+
K+
Cl-
Cl- Cl-
Zona occludens
Lumen Interstitium
Thiazide
diuretics
block
Tubular epithelium
of the early distal
tubule
Na+/Cl- co-transporter
K+/Cl- co-transporter
Na+/K+ ATPase
Key
Cl- channel
K+ channel
K+
K+
15. Pharmacodynamics
Inhibit the Na+/Cl- carrier by binding to the Cl- site and thus:
Cause up to 5% of Na+ to be excreted, producing a modest
diuresis
Possess an additional, indirect, vasodilator action (mechanism
uncertain) that contributes to their effectiveness in the treatment
of hypertension (where they are used in combination with other
antihypertensive agents)
Thiazide Diuretics (1)
Principal drugs: Bendroflumethiazide (bendrofluazide) and
hydrochlorothiazide
Prevent the dilution of filtrate in the early distal tubule
Increase the load of Na+ delivered to the collecting tubule (causing K+
loss)
Increase reabsorption of Ca2+ (cf. loop agents) (mechanism debatable)
16. Thiazide Diuretics (2)
Nephrogenic diabetes insipidus (caused by diminished
vasopressin responsiveness of the collecting ducts (paradoxically,
thiazides decrease the volume of urine – mechanism poorly
understood)
Renal stone disease (nephrolithiasis). Reduced urinary excretion
of Ca2+ discourages Ca2+ stone formation (mainly aggregates of
particles of calcium oxalate)
Severe resistant oedema (with a loop agent)
…and additionally in:
Clinical indications
Widely used in:
Mild heart failure Hypertension
Pharmacokinetics
Well absorbed from the G.I. tract
Enter nephron by the organic anion transport mechanism
(proximal tubule)
17. Thiazide Diuretics (3)
Adverse effects
Male sexual dysfunction
Hyperuricaemia – mechanism as for loop agents – may
precipitate gout
Metabolic alkalosis
Depletion of magnesium (not calcium)
Hypovolaemia and hypotension (particularly in the elderly)
Hypokalaemia, particularly likely and corrected as for loop
diuretics
Impaired glucose tolerance
18. Mechanism by which Loop and Thiazide Diuretics
Cause Potassium Loss – Relevant Physiology
Aldosterone, a steroid hormone,
acts via cytoplasmic receptors to:
1. increase synthesis of the
Na+/K+ATPase
2. increase synthesis of a protein
that activates the epithelial Na+
channel (ENaC)
increase the number of H2O channels
(aquaporins) in the cell membrane
ADH (vasopressin), a peptide
hormone, acts via G-protein
coupled receptors to:
Na+
Na+
K+
K+
Zona occludens
Lumen Interstitium
Late distal and collecting tubule
H2O
Cl-
Cl-
H2O
Na+
K+
K+ Channels (ROMK), secrete K+
into the urine in the collecting
tubule
Note that K+ effectively exchanges
for reabsorbed Na+
19. Mechanism by which Loop and Thiazide Diuretics
Cause Potassium Loss
Na+
Na+
K+
K+
Zona occludens
Lumen Interstitium
Late distal and collecting tubule
H2O
Cl-
Cl-
H2O
Na+
K+
1. Increased Na+ load caused by loop
or thiazide diuretic produces
enhanced reabsorption of Na+
2. Resulting charge separation
makes lumen more negative
and depolarizes the lumenal
vs. basolateral membrane
-ve
3. Increased driving force on K+
across the lumenal membrane
leads to enhanced secretion of
K+. (Secretion of H+ is similarly
affected)
4. Secreted K+ (and H+) ‘washed
away’ by increased urinary
flow rate – development of
hypokalaemia (and metabolic
alkalosis)
20. Mechanism of Action of the Potassium Sparing Diuretics
Spironolactone and
Eplerenone
Compete with aldosterone for binding
to intracellular receptors causing:
1. decreased gene expression and
reduced synthesis of a protein
mediator that activates Na+
channels in the apical membrane
(site 1)
2. decreased numbers of
Na+/K+ATPase pumps in the
basolateral membrane (site 2)
Amiloride and Triamterene
Block the apical sodium channel
decrease Na reabsorption
Na+
Na+
K+
K+
Zona occludens
Lumen Interstitium
Late distal and collecting tubule
H2O
Cl-
Cl-
H2O
Na+
K+
X site 1
site 2
21. Potassium Sparing Diuretics
Spironolactone and Eplerenone
Have limited diuretic action (modulated by aldosterone levels)
Competitively antagonise the action of aldosterone at
cytoplasmic aldosterone receptors, gain access to cytoplasm via
the basolateral membrane
Increase and decrease the excretion of Na+ and K+ respectively
Are well absorbed from the G.I. tract and in the case of
spironolactone rapidly metabolised to canrenone (which
accounts for most of the action of the drug)
Amiloride and Triamterene
Block lumenal sodium channels in the collecting tubules. Effect
on ion fluxes are similar to those of spironolactone
Enter the nephron via the organic cation transport system in the
proximal tubule
Triamterene is well absorbed from the G.I tract, absorption of
amiloride is poor
22. Clinical indications
The major use of potassium sparing diuretics is in conjunction
with other agents that cause potassium loss. Given alone, they
cause hyperkalaemia
Aldosterone antagonists are used in the treatment of:
Heart failure
Primary hyperaldosteronism (Conn’s syndrome)
Resistant essential hypertension
Secondary hyperaldosteronism (due to hepatic cirrhosis with
ascites)
Thiazide and loop diuretics activate the renin-angiotensin-
aldosterone system (in response to reduced blood pressure)
Aldosterone antagonists potentiate the actions of thiazide and
loop agents by blocking the effect of aldosterone