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- 1. Major extracellular and intracellular electrolytes What are electrolytes? • The body fluids are solutions of inorganic & organic solutes • The concentration, balances of the various components are maintained in order for cells and tissues to have constant environment • For homeostasis, there is a regulatory mechanisms which control pH, ionic balances, osmotic balances, etc. Major Intra- and Extracellular Electrolytes • What if internal homeostasis fails? • If body is itself unable to correct an electrolyte balance due to change in composition of fluid • Replacement therapy • Electrolytes • Acids & bases • Blood products • Carbohydrates, amino acids & proteins Fluid compartment • The electrolyte concentration will vary with particular fluid compartment. • The three compartments are : • intracellular fluid (45-50% of body weight) • interstitial fluid (12- 15% of body weight) • plasma or vascular fluid (4-5% of body weight) Abhijeet Dalvi
- 2. Fluid compartment • Extracellular fluid: includes both interstitial and vascular fluids. • Three compartments are separated from each other by membranes that are • permeable to water and many organic and inorganic solutes • nearly impermeable to macromolecules such as proteins • selectively permeable to certain ions such as Na+, K+, Mg2+ Major electrolytes • Na, Cl, K, bicarbonate, Ca, Mg, PO4 • Cl is the major anion in the ECF and has no physiological function • K, Ca, Mg • maintain membrane potential for nerve conduction and muscle contraction • generate the energy needed to maintain these potentials • do the work of body functions and movement PO4 • the main reservoir is ICF and bone • serum levels fall slowly when intake is low • numerous hormonal and homeostatic mechanism exist to keep serum levels with normal range • serum levels is low in relation to intracellular concentration • concentration in the serum controls physiological activities Electrolytes in body fluid • Ions formed when electrolytes dissolve in body fluids control the osmosis of water between fluid compartments • help maintain acid-base balance, and carry electrical current • Plasma, interstitial fluid and ICF contain varying kinds and amounts of ions • The conc. of ions is expressed as mEq/L • sodium ions are the most abundant ions in ECF: involved in impulse transmission, muscle contraction, and fluid and electrolyte balance • The level of sodium is controlled by aldosterone, ADH Electrolytes in body fluid • Chloride ions are the major anions of the ECF. • They play a role in regulating osmotic pressure and forming HCl in gastric juice. • Cl- level is controlled indirectly by ADH and by process that increase or decrease renal absorption of Na+ • Potassium ions are the most abundant cations of ICF. • They play a key role in the resting membrane potential and action potential of neurons and muscle fibers. • Help maintain ICF volume and contribute to regulation of pH. • K+ level is controlled by aldosterone. • Bicarbonate ions (HCO3 - )are the second most abundant anions in the ECF. Most important buffer in the plasma Abhijeet Dalvi
- 3. Major physiological ions Sodium • The principal cation in the extracellular fluid compartment • Responsible for maintaining normal hydration and osmotic pressure • More than adequate amount of sodium are contained in daily diet with complete absorption from intestinal tract • Excess sodium is excreted by the kidneys • Renin is a proteolytic enzyme responsible for 80-85% reabsorption of sodium at glomerular filtration • Renin cleaves linear protein and forms angiotensin I, which is cleaved to form Angiotensin II, stimulate aldesterone from adrenal cortex Sodium • Hyponatremia • Extreme urine loss as observed in Diabetes insipidus (pituitary origin) • Metabolic acidosis- sodium is excreted • Addison’s disease- decrease excretion of antidiuretic hormone, aldosterone • Diarrhea, vomiting • Kidney damage • Hypernatremia • Hyperadrenalism (Cushing syndrome) aldosterone production • Severe dehydration • Certain brain injury • Excess treatment with sodium salt Sodium • Good correlation between sodium content of tissue and hypertension • If body is unable to eliminate sodium, the concentration starts to increase & hence water will be retained in tissues to maintain osmotic balance • Edema results- puffy appearance with swelling, at lower extremities • Buildup of fluid puts added burden on heart which may be aggravated if heart is also diseased • Treatment- low salt diet, diuretics, cardiotonic drugs, etc. • Sodium free salt substitute (Neocurtasal, Co-Salt) Abhijeet Dalvi
- 4. Sodium Neocurtasal Co-salt Potassium chloride Chloine Glutamic acid Potassium chloride Potassium glutamate Ammonium chloride Calcium silicate Tricalcium phosphate Tribasic calcium phosphate Potassium iodide Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Sodium (Na+) 1.8g/Kg Table salt, salty foods, animal food, milk, baking soda, baking powder, some vegetables 3-5 g Readily absorbed, extracellular, excreted in urine & sweat, aldosterone increases reabsorption in renal tubules Buffer constituent, acid base balance, osmotic pressure, CO2 transport, cell membrane permeability, muscle irritability Dehydration, acidosis, tissue atrophy, excess leads to edema, hypertension Major Intra- and Extracellular Electrolytes Potassium • Major intracellular cation, 23 times higher than the concentration of potassium in extracellular fluid compartment • Active transport mechanism (Na+/K+pump) • During transmission of nerve impulse, potassium leaves the cell and sodium enters the cell • Potassium is rapidly absorbed, excess K+ is rapidly excreted by kidney Abhijeet Dalvi
- 5. Potassium • Hypopotassemia (Hypokalemia) • Change in myocardial function • Flaccid and feeble muscle • Low blood pressure • It can occur from vomiting, diarrhea, burns, hemorrhages, diabetic coma, IV infusion of solution lacking K+, alkalosis, over use of thiazide diuretic • Alternation in ECG, • Histological changes in myocardium Hyperpotassemia • Movement of potassium into cells as protons move out of the cell into ECF • Occur during kidney damage • Cessation of heart beat Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Potassium (K+) 2.6 g/Kg Vegetables, fruits, whole grain, meat, milk, legumes 1.5-4.5 g Readily absorbed, intracellular, excreted by kidney Buffer constituent, acid base balance, osmotic pressure, CO2 transport, membrane transport, neuromuscular irritability Acidosis, renal damage Major Intra- and Extracellular Electrolytes Calcium • The normal concentration of Ca2+ in plasma is 9.4 mg/100 mL • 99% body calcium is found in bones • Hypocalcemia is a below-normal level of Ca2+ in the extracellular fluid, and hypercalcemia is an above-normal level of Ca2+ in the extracellular fluid • Major symptoms develop when the extracellular concentration of Ca2+ declines below 6 mg/100 mL or increases above 12 mg/100 mL • Nerve and muscle tissue undergo spontaneous action potential generation • dibasic phosphate (CaHPO4), carbonate, oxalate, sulfate salts Calcium • Calcium absorption is controlled by parathyroid hormone & metabolite of vitamin D • Parathyroid hormone increases extracellular Ca2+ levels and reduces extracellular phosphate levels • vitamin D is converted to 1,25-dihydroxycholecalciferol, or active vitamin D • Active vitamin D acts to increase Ca2+ absorption across the intestinal mucosa Abhijeet Dalvi
- 6. Calcium • Hypocalcemia • Caused by hypothyroidism, Vitamin D deficiency, osteoblastic metastasis, steatorrhea, Cushing’s syndrome, acute pancreatitis, acute hyperphosphatemia • Bone degeneration- osteoporosis (treatment- increase calcium and vit. D intake, increase phosphate, administration of NaF, calcitonin) • Pagets disease- initial phase of decalcification and softening of bone followed by calcium deposition with resultant thickening of deformity (treatment- phosphate salt and or calcitonin) Calcium Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Calcium (Ca++) 22g/Kg Milk, milk products, fish bones (cooked) 0.8 g Poorly absorbed according to body need, absorbed aided by vitamin D, lactose acidity; hindered by excess fat, oxalate; parathyroid hormone mobilizes bone Ca+2 Formation of appetite in bones, teeth; blood clotting; cell membrane permeability; neuromuscular irritability Rickets (child), poor growth, osteoporosis (adults), hyperexcitability Major Intra- and Extracellular Electrolytes Magnesium • Second most plentiful cation in intracellular fluid compartment & forth most abundant cation in body • 50% of body magnesium is combined with calcium & phosphorus in bone • Essential components of many enzymes involving phosphate metabolism • Required for smooth functioning of neuromuscular system • Deficiency took place due to • Malnutrition • Dietary restriction • Chronic alcoholism • GI diseases Abhijeet Dalvi
- 7. Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Magnesium (Mg+2) 0.5 g/Kg Chlorophyl, nuts, legumes, whole grain 350mg Absorbed, competes with Ca+2 for transport Cofactor for PO4 -2 transferring enzymes, constituents of bones, teeth, decrease neuromuscular irritability Magnesium conditioned deficiency, muscular tremor, confusion, vasodilatation, hyperirritability Major Intra- and Extracellular Electrolytes Phosphate • HPO4 - is principal anion in intracellular fluid compartment • Hexose is metabolized as phosphate ester • ATP is body’s mean of storing potential chemical energy • HPO4 -2/H2PO4 - is an important buffer system • Required for proper calcium metabolism • Essential for normal tooth and bone development (hydroxyapatite) • Only dihydrogen phosphate (H2PO4 -) anion will be absorbed from intestine Phosphate • ‘ortho’ indicate the most highly ‘hydroxylated’ known form of acid Phosphoric acid Meta phosphoric acid • metaphosphoric acid refers to product resulting from release of one equivalent of water molecule intramolecularly Pyrophosphoric acid Phosphate Hypophosphatemia • Not considered as problem since balance diet has q.s. phosphate • Person receiving nutrional, caloric requirement by IV Hyperphosphatemia • In hypervitaminosis D • Renal failure due to inability to excrete phosphate into urine • Hyperthyroidism • Treatment‐ • Aluminium hydroxide gel for long term Abhijeet Dalvi
- 8. Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Phosphate( PO4-3) 12 g/Kg Milk, milk products, egg yolk, meat, whole grains, legumes,nuts 3-5 g Readily absorbed, excreted by kidney Constituents of bones, teeth, constituents of buffers, ATP, NAD, FAD, metabolic intermediates, nucleotides, phospholipids, phosphoproteins, Osteomalacia; renal rickets, cardiac arrhytmia Major Intra- and Extracellular Electrolytes Chloride • Major extracellular anion, responsible for maintaining proper hydration, osmotic pressure • Maintaining normal cation/ anion balance in vascular and interstitial fluid compartment • Chloride is being removed by glomerular filtration • Hypochloremia • Inflammation of kidney • Metabolic acidosis • Hyperchloremia Chloride • Hypochloremia • Inflammation of kidney • Metabolic acidosis in diabetes mellitus, renal failure • Prolonged vomiting with loss of chloride as a gastric acid • Hyperchloremia • In dehydration • Decreased renal blood flow in heart failure • Severe renal damage • Excessive chloride intake Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Chloride (Cl-) 50 mEq/Kg Animal foods, table salt 5-10 g/Kg as NaCl Rapid absorption, excreted in urine, high renal threshould Electrolyte, osmotic balance, gastric HCl, acid- base balance Hyperchloremic alkalosis (Pernicious vomiting) Major Intra- and Extracellular Electrolytes Abhijeet Dalvi
- 9. Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Iron (Fe++/ Fe+++) 75mg/Kg Liver, meat, egg yolk, green leafy vegetables, whole grain, enriched cereals, 10 mg male; 18 mg female Absorbed according to body need; aided by HCl, ascorbic acid Constituent of Hb, myoglobin, catalase, ferredoxin, cytochrome, electron transport, enzyme cofactor Anemia, hypochromi; c pregnancy demands, excess leads to hemochromatosis Major Intra- and Extracellular Electrolytes Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Iodine (I-) Seafoods, iodized salt 140 g male; 100 g female Concentrates in thyroid Constituents of thyroxine, triiodothyronine , regulates extracellular oxidations Goiter (hyperthyroidism), creatinism Major Intra- and Extracellular Electrolytes Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Zinc (Zn+2) 28 mg/Kg Liver, pancreas, shelllfish, widely distributed in animal, plants tissues 10-15 mg 1-2 mg absorbed Constituents of insulin, carbonic anhydrase, carboxypeptidase, lactic dehydrogenase, alkaline phosphatase Anemia, stunned growth, hypogonadism Major Intra- and Extracellular Electrolytes Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Copper (Cu++) 2mg/Kg Liver, kidney, egg yolk, whole grain 2-3 mg Limited absorption, transport by ceruloplasmin, stored in liver, excreted via bile Formation of Hb; constituent of oxidase enzyme (tyrosinase, cytochrome oxidase, ascorbic acid oxidase) Hypochromic anemia, excessive hepatic storage in Wilson disease Major Intra- and Extracellular Electrolytes Abhijeet Dalvi
- 10. Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Cobalt (Co+2) 3mg Liver, pancreas 1-2 mg Limited absorption; stored in liver; excreted via bile Constituent of vitamin B12 Anemia in animals; deficiency as vitamin B12 – pernicious anemia; Excess leads to polycythemia (increase in no. of RBCs) Major Intra- and Extracellular Electrolytes Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Molybde num (Mo) 5mg/Kg Liver, kidney, whole grain, legumes, leafy vegetables Trace Readily stored & excreted in urine and bile Constituent of xanthin oxidase, alcohol dehydrogenase Unknown Major Intra- and Extracellular Electrolytes Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Chromiu m (Cr+3) Liver, animal and plant tissue traces Involved in carbohydrate utilization Unknown, possible relation to cardiovascular disease Major Intra- and Extracellular Electrolytes Element & Total amount in human body Best food source RDA Absorption & Metabolism Principle metabolic functions Clinical manifestations of deficiency Fluoride (F) Seafoods, some drinking water 1mg 1ppm in drinking water Easily absorbed, excreted in urine, deposited in bones, teeth Constituent of fluoroapetite- tooth enamel Dental caries, osteoporosis, excess leads to mottled enamel Major Intra- and Extracellular Electrolytes Abhijeet Dalvi
- 11. Electrolytes used in replacement therapy • Sodium replacement- • Sodium chloride* • It is a salt of extracellular fluid • Uses range from replacement therapy • Manufacture of isotonic solutions to flavour enhancers • For isotonicity salt conc. should be 0.9% w/v • Isotonic solutions are used as wet dressing, irrigating body cavities, or tissues, as injections Electrolytes used in replacement therapy • Sodium replacement- • Sodium chloride(NaCl, Mol. Wt. 58.44)* • Colourless cubic crystals or white crystalline powder, saline taste, deliquescent • Soluble in water, slightly more soluble in boiling water, soluble in glycerine, slightly soluble in alcohol • Buildup of excessive extracellular fluid due to administration of isotonic sodium chloride may lead to pulmonary and peripheral edema Electrolytes used in replacement therapy • Sodium replacement- • Hypotonic solutions are administered for maintenance therapy • Dose- oral , 1g three time a day • IV infusion, 1 L of 0.9% NaCl solution, • Topically to wounds, body cavities, as 0.9% solution for irrigation • First aid treatment in poisoning Electrolytes used in replacement therapy • Potassium replacement- • Potassium chloride(KCl, Mol.Wt. 74.56) • Colourless, elongated, prismatic, or cubic crystals, or white granular powder • Odourless, saline taste, stable in air • Freely soluble in water, more soluble in boiling water, insoluble in alcohol • KCl inj., KCl tab., Ringer inj., Lactated ringer inj., Lactated potassium saline inj. Abhijeet Dalvi
- 12. Electrolytes used in replacement therapy • Potassium replacement- • Potassium chloride(KCl, Mol.Wt. 74.56) • It’s drug of choice for oral replacement of potassium, preferably as a solution • It is irritating to GIT, hence must be given in well diluted • In severe hypopotassemia, injections of KCl should be give with close monitoring of serum K+ concentration, ECG, urinary output • As an antidote in digitalis intoxication, Menier’s syndrome (inner ear disorder causing vertigo) • As adjunct to drug used in treatment of Mysthenia gravis (skeletal muscle weakness) Electrolytes used in replacement therapy • Calcium gluconate(Mol wt. 430.88) • White, crystalline, odourless, tasteless, granules or powder, stable to air • Solution are neutral to litmus, sparingly soluble in water, freely soluble in boiling water, and insoluble in alcohol, many organic solvents • Choice for hypocalemia- when given orally, its is non- irritation, hence orally as well as IV can be given Physiology of acid base balance • The normal pH of systemic arterial blood is 7.35-7.45 • Arterial blood is 7.4 • Venous blood and interstitial fluid is 7.35 • Intracellular fluid is 7.0 • Important part of homeostasis because cellular metabolism depends on enzymes, and enzymes are sensitive to pH. • The important buffer systems include proteins, carbonic acid‐bicarbonate buffers • pH is maintained by buffers. and phosphates. Acid‐Base Balance • pH is maintained by buffers. and phosphates. The important buffer systems include proteins, carbonic acid‐bicarbonate buffers • Homeostasis of pH is maintained by buffer systems, via exhalation of carbon dioxide, and via kidney excretion of H+ and reabsorption of HCO3 . ‐ • The overall acid‐base balance is maintained by controlling the H+ conc. of body fluids, especially ECF. Abhijeet Dalvi
- 13. Physiology of Acid Base Balance • The principal buffer systems of the body fluid are • Protein buffer system • Carbonic acid- bicarbonate buffer system • Phosphate buffer system Physiology of Acid Base Balance • Protein buffer system • Most abundant buffer in intracellular fluid and blood plasm • e.g. Hb is a good buffer within red blood cells; albumin is main protein in blood plasma • Proteins are composed of amino acids, organic molecules that contain at least one carboxyl group and at least one amino group, functional components of protein system Physiology of Acid Base Balance • Protein buffer system • Most abundant buffer in intracellular fluid and blood plasm • e.g. Hb is a good buffer within red blood cells; albumin is main protein in blood plasma Electrolyte Combination therapy • Inability of patient to take food • Infusions containing Glucose and saline • Mixture of electrolyte if patient is deficient of them • Fluid maintenance • Electrolyte replacement • IV administration • Fluid maintenance : 5% glucose, help reduce urea, ketone body, phosphate, (starvation) • Fluid loss, vomitting, diarrohea, dehydration • Sod. Lactate inj, Compound NaCl inj, compound Sod. Lactate inj. Abhijeet Dalvi
- 14. Electrolytes in combination therapy • Infusions • In short term therapy, infusion of std. glucose & saline is adequate • when deficits are severe, solutions containing additional electrolytes are required • Fluid maintenance- maintenance therapy with IV fluid to supply normal requirement of water, electrolytes • All maintenance dose should contain atleast 5% dextrose • This minimizes buildup of those metabolites associated with starvation- urea, phosphate, ketone bodies Electrolytes in combination therapy • Electrolyte replacement- when there is heavy loss of water & electrolytes as in prolonged fever, severe vomiting, diarrhea Maintenance solution Rapid initial replacement therapy Subsequent replacement therapy 25‐30 mEq/l Na 130‐150 mEq/l Na 40‐120 mEq/l Na 15‐20 mEq/l K 4‐12 mEq/l K 16‐35 mEq/l K 22 mEq/l Cl 98‐ 109 mEq/l Cl 30‐103 mEq/l Cl 20‐23 mEq/l HCO3 28‐55 mEq/l HCO3 16‐53 mEq/l HCO3 3 mEq/l Mg 3‐5 mEq/l Ca 0‐5 mEq/l Ca 3 mEq/l P 3 mEq/l Mg 3‐6 mEq/l Mg 0‐13 mEq/l P Ringers’ solution (IP 2007) • It is a Compound Sodium Chloride Solution • solution containing • 0.86 per cent w/v of Sodium Chloride, • 0.03 per cent w/v of Potassium Chloride and • 0.033 per cent w/v of Calcium Chloride in Purified Water • Is a clear, colourless solution. Oral Rehydration Salt (ORS) • Contains anhydrous glucose, sodium chloride, potassium chloride and sodium bicarbonate/sodium citrate • Intended for the prevention and treatment of dehydration due to diarrhoea, including maintenance therapy • Are dry preparations to be mixed in specific amounts of water • Used for oral rehydration therapy • Home version: 1 tablespoon salt + 2 tablespoons sugar in 1 L of water • ORS and zinc are recommended by the WHO and UNICEF to be used collectively to ensure the effective treatment of diarrhoea • ORS replaces the essential fluids and salts lost through diarrhoea • Zinc decreases the duration and severity of an episode and reduces the risk of recurrence in the immediate short term Abhijeet Dalvi
- 15. Oral Rehydration Salt (ORS) • ORS and zinc are highly effective and affordable products for treatment of childhood diarrhoea that could prevent deaths in up to 93% of diarrhoea cases. • ORS is included in WHO’s Essential Medicines List, Priority Medicines for Mothers and Children and Life-Saving • Commodities for Women and Children. • In 2005, WHO and UNICEF recommended a switch from the standard ORS to an improved lower-osmolarity formulation (with a total osmolarity of 245 mOsm/L, instead of the previous standard ORS with a total osmolarity of 311 mOsm/L), be combined with zinc supplementation. • ORS is a powder for dilution in 200 mL, 500 mL, and 1 L. Products are packed in hermetically sealed, laminated • sachets. The sachets may be made of multiply laminations with aluminum foil or polyethylene foil. • The multiply laminated aluminum foil sachet is usually recommended for ORS. A compound of polyethylene (inside), aluminum (middle), and polyester or any other suitable coating compound (outside) has proved to be a satisfactory combination for packing ORS. ORS (IP2007) • Oral Rehydration Salts are dry, homogeneously mixed powders containing Dextrose, Sodium Chloride, Potassium Chloride and either Sodium Bicarbonate or Sodium Citrate for use in oral rehydration therapy after being dissolved in the requisite amount of water • may contain suitable flavouring agents and, where necessary, suitable flow agents in the minimum quantity required to achieve a satisfactory product. • may not contain artificial sweetening agents like mono- and/or polysaccharides. • If saccharin/saccharin sodium or aspartame is used in preparations meant for paediatric use, the concentration of saccharin should be such that its daily intake is not more than 5 mg/kg of body weight and that of aspartame should be such that its daily intake is not more than 40 mg/kg of body weight. ORS (IP 2007) • Strength. A formulation of reduced osmolarity (given below) recommended by the World Health • Organization (WHO) for the Diarrhoeal Diseases Control Programme, and of the United Nations • Children’s Fund (UNICEF) • Composition of the formulation in terms of the amount, in g, to be dissolved in sufficient water to produce 1000 ml • Sodium chloride 2.6 • Dextrose OR 13.5 • Dextrose Monohydrate 14.85 • Potassium chloride 1.5 • Sodium citrate 2.9 ORS • These criteria are listed below; they refer to the desired characteristics of the solution after it has been prepared according to the instructions on the packet: • Total substance concentration (including that contributed by glucose) should be within the range of 200–310 mmol/L. • ■ Individual substance concentration: • Glucose should at least equal that of sodium but should not exceed 111 mmol/L. • Sodium should be within the range of 60–-90 mEq/ or mmol/L. • Potassium should be within the range of 15–25 mEq/ or mmol/L. • Citrate should be within the range of 8–12 mmol/L. • Chloride should be within the range of 50–80 mEq/ or mmol/L. Abhijeet Dalvi
- 16. Acids, Bases and Buffers: Buffer equations and buffer capacity in general, buffers in pharmaceutical systems, preparation, stability, buffered isotonic solutions, measurements of tonicity, calculations and methods of adjusting isotonicity. Major extra and intracellular electrolytes: Functions of major physiological ions, Electrolytes used in the replacement therapy: Sodium chloride*, Potassium chloride, Calcium gluconate* and Oral Rehydration Salt (ORS), Physiological acid base balance. Dental products: Dentifrices, role of fluoride in the treatment of dental caries, Desensitizing agents, Calcium carbonate, Sodium fluoride, and Zinc eugenol cement. Abhijeet Dalvi