Absorption is the movement of a drug from the administration site into the bloodstream. The rate and amount of absorption determines when drug effects begin and how intense they are. Absorption is affected by factors like dissolution, surface area, blood flow, lipid solubility, and pH. Intravenous administration has no barriers to absorption and instant onset, while oral absorption is slow and variable due to passing through the GI tract. The degree and rate of absorption ultimately influence a drug's onset, peak level, duration, and bioavailability.
Kia New SORENTO 2014: Công nghệ mới - Đẳng cấp mới (Hotline: 0909016946)muaxegiatot.com
NEW SORENTO 2014 "CÔNG NGHỆ MỚI, ĐẲNG CẤP MỚI"
- Ngoại thất thiết kế mới với kiểu dáng hiện đại và thể thao
- Động cơ mạnh mẽ tiết kiệm nhiên liệu, trang bị máy dầu với công suất và mô men soắn vượt trội
- Nội thất thiết kế tinh tế và sang trọng, hạn chế tiếng ồn, không gian thoải mái
- An toàn hơn với 8 túi khí, hệ thống cân bằng điện tử, khung xe kết cấu thép cường lực đạt tiêu chuẩn an toàn 5 sao của NHTSA (Mỹ)...
Vui lòng liên hệ để biết thông tin chi tiết.
Bioavailability and bioequivalence
Bioavailability-
Whenever a drug is given by oral route it has to go through certain pathway to reach the systemic circulation. Eg. If 100 mg drug is given orally, and if 80 mg is absorbed and 20 mg gets excreted then 80 mg absorbed drug reaches liver through portal system. In liver it gets metabolized, here if 30 mg gets metabolized by the liver 50 mg reaches the systemic circulation in the unchanged from. But Bioavailability is expressed in mg it has to be expressed in fraction. So Bioavailability is basically the fraction of unchanged from of the drug that reaches the systemic circulation following administration by any route.
As the drug given by intravenous route reaches directly into the systemic circulation. So the Bioavailability of drug given i.v is 100 %. % Bioavailability can be calculated as- Area under the curve (AUC oral)/ (AUC i.v) *100.
Bioavailability depends on both the rate and extent of absorption.
Rate of absorption depends on- site of adminstration and the drug formulation.
Extent (amount) of absorption depends on- route of drug administration
Factors affecting absorption and Bioavailability-
Pharmaceutical and pharmacological factors:
Pharmaceutical factors include- particle size, crystal from, salt form, water of hydration, Nature of excipients and adjuvants, degree of ionisation.
Pharmacological factors- gastric emptying & g.i mobility, g.i diseases, food and other substances, first-pass effect, Drug-drug interaction, pharmacogenetics, miscellaneous factors like route of administration, area of absorbing surface, state of circulation at site of absorption.
Kia New SORENTO 2014: Công nghệ mới - Đẳng cấp mới (Hotline: 0909016946)muaxegiatot.com
NEW SORENTO 2014 "CÔNG NGHỆ MỚI, ĐẲNG CẤP MỚI"
- Ngoại thất thiết kế mới với kiểu dáng hiện đại và thể thao
- Động cơ mạnh mẽ tiết kiệm nhiên liệu, trang bị máy dầu với công suất và mô men soắn vượt trội
- Nội thất thiết kế tinh tế và sang trọng, hạn chế tiếng ồn, không gian thoải mái
- An toàn hơn với 8 túi khí, hệ thống cân bằng điện tử, khung xe kết cấu thép cường lực đạt tiêu chuẩn an toàn 5 sao của NHTSA (Mỹ)...
Vui lòng liên hệ để biết thông tin chi tiết.
Bioavailability and bioequivalence
Bioavailability-
Whenever a drug is given by oral route it has to go through certain pathway to reach the systemic circulation. Eg. If 100 mg drug is given orally, and if 80 mg is absorbed and 20 mg gets excreted then 80 mg absorbed drug reaches liver through portal system. In liver it gets metabolized, here if 30 mg gets metabolized by the liver 50 mg reaches the systemic circulation in the unchanged from. But Bioavailability is expressed in mg it has to be expressed in fraction. So Bioavailability is basically the fraction of unchanged from of the drug that reaches the systemic circulation following administration by any route.
As the drug given by intravenous route reaches directly into the systemic circulation. So the Bioavailability of drug given i.v is 100 %. % Bioavailability can be calculated as- Area under the curve (AUC oral)/ (AUC i.v) *100.
Bioavailability depends on both the rate and extent of absorption.
Rate of absorption depends on- site of adminstration and the drug formulation.
Extent (amount) of absorption depends on- route of drug administration
Factors affecting absorption and Bioavailability-
Pharmaceutical and pharmacological factors:
Pharmaceutical factors include- particle size, crystal from, salt form, water of hydration, Nature of excipients and adjuvants, degree of ionisation.
Pharmacological factors- gastric emptying & g.i mobility, g.i diseases, food and other substances, first-pass effect, Drug-drug interaction, pharmacogenetics, miscellaneous factors like route of administration, area of absorbing surface, state of circulation at site of absorption.
Whenever a drug is given orally it has to go through certain pathway to reach systemic circulation.
E.g out of 100 mg drug given orally if 80 mg gets absorbed & 20 gets excreted. 80 mg of absorbed drug then reaches the liver through portal vein. Liver is highly saturated with enzymes so it doesn't allow the drug to pass freely through it without metabolizing certain amount of drug. . So if 30 mg of absorbed drug gets metabolized in the liver remaining 50 mg of drug reaches the systemic circulation in the unchanged form. But Bioavailability is never expressed in mg it is always expressed in fraction. So Bioavailability is basically the fraction of unchanged from of the drug that reaches the systemic circulation following administration by any route.
Whenever drug is given intravenously 100% drug reaches the systemic circulation in an unchanged form. So the Bioavailability of the drug given intravenously is 100%, while that of the drug given orally is < 100%
Bioavailability of a drug depends on the rate and extent of absorption.
Rate of drug administration is determined by: site of drug administration and drug formulation.
Extent (amount) of drug absorption is determined by: route of drug administration.
Factors affecting drug absorption and Bioavailability- There are various pharmaceutical and pharmacological factors that affect the drug absorption.
FIRST PASS METABOLISM:-
The drug given orally first pass through GI wall and then reaches the liver through portal system. The drug can also be metabolized in the gut wall CYP3A4 enzyme which is a substrate for P-gp {P-glycoprotein (P-gp) is an active transporter which pumps drug out of the gut wall cells back into the gut lumen against the concentration gradient.) Normally, drug enters the intestinal lumen by passive diffusion (i.e along the concentration gradient). But P-gp causes drug efflux or drug wastage (i.e against the concentration gradient); The amount of drug that disappears contribute first pass metabolism. But first pass metabolism occur in LIVER > INTESTINE.
Some amount of drug while passing through the liver gets metabolized in the liver for the first time before reaching the systemic circulation this known as first pass metabolism.
Bioequivalence- it as comparison of 2 different brand products of a same drug.
E.g. if Drug company X designs a new drug - (BRANDED DRUG) it gets patency for suppose 20 yrs. So that no other company can legally copy this drug. But once the patency expires any other company can legally copy this drug (GENERIC DRUG) but requires approval by FDA. and FDA asks for BIOEQUIVALENCE certificate (i.e it checks if the compound produced by other company is equivalent to that of BRANDED DRUG.) It has to prove that amount as well as rate of absorption is similar. No company can copy the drug 100% as it is. therefore the acceptable range is +/- 20-25%. The drug can be chemically, pharmaceutically, Therapeutically & clinically equivalent.
Thank you
A brief presentation on the factors affecting bioavailability of drugs along with a quick overview on what is bioequivalence, clinical equivalence, therapeutic equivalence, chemical equivalence and pharmaceutical equivalence.
Drug administration is a critical aspect of healthcare, influencing the efficacy, safety, and patient experience associated with pharmaceutical interventions. The choice of drug administration route depends on various factors, including the drug's properties, the patient's condition, and the desired therapeutic outcome. In this comprehensive overview, we will delve into the various routes of drug administration, exploring their advantages, disadvantages, and specific considerations.
1. Oral Route
The oral route is the most common and convenient method of drug administration. Medications are typically ingested in the form of tablets, capsules, liquids, or powders. The digestive system processes the drug, allowing for absorption through the gastrointestinal tract.
Advantages:
- Patient convenience: Oral medications are easy to administer and are often preferred by patients.
- Self-administration: Patients can take oral medications without the need for healthcare professionals.
- Economical: Oral medications are generally cost-effective.
Disadvantages:
- Variability in absorption: Absorption can be influenced by factors such as food, gastric emptying, and pH levels, leading to variability in drug levels.
- First-pass metabolism: Drugs undergo metabolism in the liver before entering the systemic circulation, potentially reducing bioavailability.
Considerations:
- Patient compliance: Oral medications may be unsuitable for non-compliant patients or those with difficulty swallowing.
- Drug stability: Some drugs may degrade in the acidic environment of the stomach.
2. Sublingual and Buccal Routes
These routes involve placing medications under the tongue (sublingual) or against the cheek and gum (buccal). Absorption occurs through the mucous membranes, bypassing the gastrointestinal system and first-pass metabolism.
Advantages:
- Rapid absorption: Sublingual and buccal routes offer faster absorption compared to the oral route.
- Avoidance of first-pass metabolism: The drugs enter the systemic circulation directly, enhancing bioavailability.
Disadvantages:
- Limited drug types: Not all drugs are suitable for sublingual or buccal administration due to taste, irritation, or rapid metabolism.
- Inconvenience: Some patients may find it challenging to keep medications in the sublingual or buccal area.
Considerations:
- Patient preference: The sublingual and buccal routes are often used for drugs requiring rapid onset of action, such as nitroglycerin.
3. Rectal Route
Rectal administration involves inserting medications into the rectum, where absorption occurs through the rectal mucosa. Suppositories, enemas, and rectal solutions are common dosage forms for this route.
Advantages:
- Bypassing first-pass metabolism: Similar to sublingual and buccal routes, rectal administration avoids the liver's first-pass effect.
- Useful in vomiting patients: Rectal administration
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Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
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Knee anatomy and clinical tests 2024.pdfvimalpl1234
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2. Why is absorption important?
• The RATE of absorption determines how soon
the drug’s effects will begin.
• The AMOUNT of absorption determines the
intensity of the effects.
• The RATE and AMOUNT of absorption vary
depending on several factors, many of them
dependant on administration site.
3. ABSORPTION FACTORS
• Rate of Dissolution
• Surface Area
• Blood Flow
• Lipid Solubility
• pH Partitioning
4. Intravenous
• No barriers to absorption
• Instantaneous
• Advantages:
– Rapid onset, control, large dosages, reduced
irritation
• Disadvantages:
– Irreversible, expensive, inconvenient, difficult,
high risk, drug-specific
5. Intramuscular / Subcutaneous
• Must pass the capillary wall
• Rapid or slow absorption
• Advantages:
– Use with poorly soluble drugs, use with depot
preparations
• Disadvantages:
– Discomfort, inconvenient, potential for injury
6. Oral
• Must pass the capillary wall and GI tract
• Slow and variable absorption
• Advantages:
– Easy and convenient, inexpensive, self-med,
potentially reversible
• Disadvantages:
– Variable, inactivation, gastrointestinal side
effects, patient adherence
9. Nursing Implications of Absorption
• The degree and rate of absorption are
important because they are ultimately going
to affect the drug’s:
– onset of activity
– peak level
– duration
– bioavailability (the percentage of drug absorbed
into the systemic circulation for activity)
10. References
Comerford, K. (2004). Fundamentals of nursing pharmacology. In Straight A's in
nursing pharmacology (pp. 1-15). Springhouse, PA: Lippincott Williams & Wilkins.
Drug absorption, distribution and elimination: Pharmacokinetics. (n.d.). In
Columbia.edu. Retrieved September 6, 2012, from
http://www.columbia.edu/itc/gsas/g9600/2004/GrazianoReadings/Drugabs.pdf
Kelly, j. (2001, Dec. 1). Minimising potential side-effects of medication at different
ages. Nursingtimes.net. Retrieved from http://www.nursingtimes.net/minimising-
potential-side-effects-of-medication-at-different-ages/197723.article
Lehne, R. (2013). Orientation to pharmacology. In Pharmacology for nursing care (8th
ed., pp. 1-4). St. Louis, MO: Elsevier Saunders.
Editor's Notes
Hi! My name is John and I’m going to discuss the topic of Absorption. Absorption simply means the movement of a drug from the administration site into the blood.
So why is absorption important? Understanding the factors that influence the rate and amount of absorption will be important in understanding how the medications will affect the patient. The faster the rate of drug absorption, the faster the drug will begin working. And the more of a drug that is absorbed, the more of an effect that drug will have on the patient. Therefore you can see how having a good understanding of the factors that affect absorption will be critical.
There are 5 primary factors that affect drug absorption: Rate of Dissolution, Surface Area, Blood flow, Lipid Solubility, and pH partitioning. Each of the first three factors has a direct relationship with drug absorption. Therefore, a rapidly dissolving drug, a large surface area, and high rate of blood flow can each lead to a high rate of absorption. Drugs that have high lipid solubility are more rapidly absorbed. pH partitioning affects how a drug moves from the site of administration into the blood plasma. As nurses, we are mostly concerned with the first three factors as those are the factors we can have the greatest impact on. =================================================================================There are 5 key factors that affect absorption. For a drug to be absorbed it must be dissolved. Therefore the faster a drug dissolves the faster it can be absorbed. Surface area is a major factor in determining absorption rate. The greater the available surface area, the more rapid absorption will be. Blood flow is important because sites that have rapid blood flow will have a faster rate of absorption. Blood that has absorbed the drug will circulate quickly, allowing the drug to be absorbed by blood that is drug-free. Lipid Solubility is a factor because drugs coming from certain administration sites have to pass through cell membranes that are made up of a lipid bilayer. Drugs that are not lipid soluble cannot make it through these membranes. pH partitioning affects absorption, as the difference in the pH levels of the blood plasma and site of administration will have an effect on drug absorption.
However, those factors have very little to do with our first method of administration. When giving drugs intravenously there are no barriers to absorption! Intravenous drugs enter the blood stream immediately. This is the most efficient method of drug delivery and has several advantages like immediate onset and greater control of the medication administered. There are also many risks associated with this direct path into the blood stream so a nurse needs to be cautious and precise when giving IV drugs.=============================================================================Intravenous therapy refers to the infusion of substance directly into a vein. There are no barriers to absorption with IV medications and it occurs instantaneously. The advantages of IV therapy include rapid onset, precise control over the amount of drug entering the blood, suitability for use with large volumes of fluid, and suitability for irritant drugs. The disadvantages include that absorption is irreversible, expensive, and inconvenient, as well as the medications are poorly suited for self-administration, thee is a risk for fluid overload, infection, and embolism, and finally, the drugs administered must be water soluble.
Intramuscular and subcutaneous injections are also efficient ways of giving medication. However there are some barriers to absorption with this method. Absorption is affected by the water solubility of the drug and the blood flow to the site of injection. Drugs that are highly water soluble will be rapidly absorbed. If blood flow is high to the injection site then absorption will be rapid. An advantage to this method is that drugs that don’t dissolve very well can be administered through an IM or SUBQ injection but cannot be given intravenously. Unlike IV therapy, intramuscular and subcutaneous medications must first pass through the capillary wall, which is fairly easy to pass. The rates of absorption are variable, which occurs rapidly for water soluble drugs and slowly with poor soluble drugs. The advantages for SQ/IM administration include the permitted use of poorly soluble drugs and the use of depot preparations. The disadvantages for this type of administration include possible discomfort, inconvenience, and the potential for injury.
Oral medications are typically the most commonly used and prescribed medications today. Medications administered orally must pass both the capillary wall and the GI tract. The absorption of oral medications is the slowest and most variable of all the methods. The advantages include ease and convenience, an inexpensive price tag, the results are potentially reversible, and finally, the medications are ideal for self-administration. The disadvantages include variability, inactivation, GI side effects, and patient adherence.
Topical medications are useful for treating external ailments. Applying medication directly to the site can enhance absorption. Rectal and vaginal suppositories allow for local treatment of problems. Topical medications and rectal suppositories are also alternate routes for absorption of medication into the blood stream. Inhalants are useful for treating conditions involving the lungs, and allow for rapid absorption of the drug. Some conditions require direct injection of the drug into sites like joints, the heart, and nerves.Some additional routes include; topical medications, rectal and vaginal suppositories, inhalants, and direct injection.
Drug absorption has special concerns when considering very young and very old patients. To start with neonates have prolonged and erratic gastric emptying. This means that drugs that are absorbed in the stomach have much more time to be absorbed increasing the dose that gets to the target. This can lead to increased risk of toxicity. Drugs that are absorbed in the intestine may be delayed and absorption cannot be predicted.IM injection absorption in neonates is also slow and erratic due to decreased blood flow to the muscles. However, infancy brings about a much more rapid absorption of IM drugs. Once again increasing the risk of toxicity.Infants also have a more rapid absorption of transdermal medications. This is due to thin skin and increased blood flow to the skin. Yet again increasing the risk of toxicity.Once the pediatric patient reaches childhood(age 1 and over), these routes of absorption start to level out to adult levels.
So how does absorption affect drug therapy? What factors do you need to know? Here are the main points. Factors that influence the degree and rate of absorption are the administration route, the patient’s age and physical condition, lipid or water solubility, and the drug’s mechanism of action.These factors will ultimately affect the drug’s onset of activity, peak level, duration, and bioavailability. … each of which are directly related to the drug therapy desired.