Post on 14-Jan-2016
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Haematopoietic agents, Vitamins & Antioxidants
Dr. Rishi Pal
Assistant Professor
Department of Pharmacology
Haematopoietic system
Erythrocytes Leukocytes Thrombocytes
Exogenous nutrients Endogenous nutrients
Types of anaemia
Microcytic hypochromic anaemia Megaloblastic anaemia Pernicious anaemia Haemolytic anaemia Aplastic anaemia Sickle cell anaemia Sideroblastic anaemia
Iron deficiency anaemia
Pallor Fatigue Dizziness Exertional dyspnoea Iron deficiency Dietary deficiency Faulty absorption, transport and storage Excessive blood loss Worm infestation
Max iron absorption: duodenum & jejunum Haem iron & non haem iron (Fe+++) Ascorbic acid, SH, Succinic acid facilitate
conversion of Fe+++ to Fe++ form
Body requirement of iron Hb has 33% of iron (50 mg in 100 ml of
blood) Daily requirement
Male: 0.5-1 mg
Female: 1-2 mg
Children: 25 mg
Pharmacokinetics of iron
Iron absorbs by active transport across intestinal mucosa.
Converted Fe2+ to Fe3+
Apoprotein-iron complex (ferritin) Release on demand Absorption depends on apoprotein to ferritin ratio. Transferrin binds with free Fe2+ or Fe3+ from ferritin
and carries to bone marrow
Haemosiderin granules seen with iron overload & gives rise to haemosiderosis or bronze diabetes.
Treatment of iron defeciency anaemia
Oral iron therapy: ferrous salts of sulfate,fumerate,gluconate, lactate, succinate and
glycine sulfate etc.
Ferric salts: ferric ammonium citrate, iron polysaccharide and ferric hydroxide polymaltose complex.
Ferrous salts better absorbed than ferric salts.
Ferrous salts: 100mg provides 20% of elemental iron Ferrous fumerate: 33% Ferrous sulfate:19% Ferrous succinate: 12% Adult: 200mg of elemental iron administered in 2-3
divided doses after meal Children:3-5mg/kg in 3 divided doses 325mg tablets of ferrous sulfate, thrice a day
Ferrous sulfate: FERSOLATE 200mg tab Ferrous fumerate: NORI-A 200mg tab Ferrous gluconate:FERRONICUM 300mg tab Collodial ferric hydroxide: NEOFERRUM 200
mg tab. 400mg/5ml syrup
Parenteral iron therapy
For those who are not able to absorb oral iron preparations.
Not able to maintained iron content because of acute/chronic blood loss or GITdisorders like sprue or inflammatory bowel disease.
Iron-dextran: iv or im (50mg/ml) Iron sucrose complex: iv or im Iron-sodium gluconate: iv or im Iron-sorbitol-citrate: only im
Vitamin B12
Cyanocobalamine Hydroxycobalamine Methylcobalamine 5’ deoxyadenosyl cobalamine
Pharmacokinetics of cobalamine Intrinsic factor (IF) Transcobalamine-II Metabolic functions Therapeutic uses Daily requirement: 2-3 ug/day Therapeutic dose: 100-1000ug/day i.m
Cyanocobalamine REDISOL, MACRABIN 100µg, 500µg/day Hydroxocobalamine REDISOL-H, MACRABIN-H 500µg, 1000µg
per vial inj. Methylcobalamine METHYLCOBAL 500µg tab, NEUROKIND-
OD 1500µg tab., 500µg/ml inj.
Folic acid
Pteroylglutamic acid Pharmacokinetics Metabolic functions Deficiency Therapeutic uses Daily requirement: 50µg Therapeutic doses: 1-5mg/day
Folic acid
FOLVITE, FOLITAB 5mg tab Folinic acid
RECOVORIN 15 mg tab., 75mg/ml, 10mg/ml inj.
Haematopoietic growth factors
Erythropoietin: epoietin 100 IU/kg s.c or i.v 3 times a week, darbepoetin.
Preparations available EPOX, ZYROP,EPREX 2000IU, 4000IU/ml
inj. Colony stimulating factor (CSF) G-CSF & GM-CSF Filgrastim & pegfilgrastim 300µg/inj.
Megakaryocyte growth factors Interleukin-11
Vitamins
Fat soluble vitamins: A, D, E and K Water soluble vitamins B-complex group: B1,B2,B3,B5,B6 and Biotin
Haematopoietic B-complex vitamins
Folic acid and cyanocobalamin
Non B-complex group: Ascorbic acid (vitamin-C)
Vitamin A (Retinol)
Dietary sources Physiological role a) Proper vision in dim light b) Structural integrity of epithelial cells Deficiency a) Night blindness b) Keratomalacia c) Xerophthalmia
Vitamin A analogs
Beta-Carotene: 30-300µg/day
Tritinoin
Isotritinoin:500µg/kg in 2 divided doses for 3-4 months
Etretinate: For refractory Psoriasis
Tazarotene and Bexarotene
Daily requirements
Adult doses: 4000IU/day Therapeutic doses
50,000IU-1 lac IU orally for 3 days Hypervitaminosis Preparations available AROVIT 50,000IU tab., 1 lacIU/2 ml inj AQUQSOL-A 50,000IU cap
Vitamin E(Tocoferol)
Dietary sources Phyiological role Deficiency symptoms: Peripheral
neuropathy,Sterility in males and Recurrent abortion in females
Therapeutic doses:400mg/day Nocturnal muscle cramps:400mg/day for 6-12
weeks
Vitamin E contd.
Fibrocystic breast disease:600mg/day for 3-6 months
Intermittent claudication:400mg/day for 12-15 weeks
Acanthocytosis:100mg/week i.m inj
Thiamine (Vitamin B1)
Dietary sources Physiological role Deficiency symptoms Dry Beri-Beri,Wet Beri-Beri Therapeutic doses:100mg/day i.m or iv then
5-10mg/day orally as maintenance dose Preparations available:BERIN 50mg-100mg
tab,100mg/ml inj,BENALGIS 75mg tab
Riboflavin (Vitamin B2)
Dietary sources Physiological role Deficiency symptoms:
Glossitis,Cheilosis,Cataract formation Therapeutic doses:5-20mg/day Preparations available:RIBOFLAVIN10mg
tab,10mg/ml inj.
Niacin (Vitamin B3)
Dietary sources Physiological role Deficiency symptomsPellagra(Dermatitis,Dementia,Insomnia,Diarrhoea,Deat
h) Prophylactic doses:15-20mg/day Therapeutic doses:200-500mg/day oral Preparations available:NEASION-SR,NIALIP
375mg,500mg tab
Pantothenic acid (Vitamin B5)
Dietary sources Physiological role Deficiency symptoms:Intermittent diarrhoea,
Leg cramps,Paraesthesia,Insomnia Therapeutic doses:50-100mg/day
Pyridoxine (Vitamin B6)
Dietary sources Physiological role Deficiency symptoms
Peripheral neuropathy,Stomatitis,Precipitation of epilepsy and growth retardation.
Prophylactic doses:2-5mg/day Therapeutic doses:50-200mg/day Preparations
available:PYRIDOX,BENADON50mg tab
Ascorbic acid (Vitamin C)
Dietary sources Physiological role Deficiency symptoms: Scurvy (defect in collegen
formation) Prophylactic doses:50-500mg/day Therapeutic doses:1-1.5g/day As antioxidant:100mg/day Haematinic formulations 150mg/day Preparations
available:CELIN,CHEWCEE,REDOXON 500mg tab
Antioxidants
Erythropoietin
Cytokine produced in juxtatubular cells in the kidney and also in macrophages.
Produced by recombinant technology. Available as epoeitin α and β. 25-100 IU/kg, s.c. or i.v. 3 times a week.
Uses of Erythropoietin
Anaemia due to: Chronic renal failure. Cancer chemotherapy. AIDS. Premature infants. Blood transfusion Adverse effects: flu-like symptoms, mild
hypertension, encephalopathy, occasionally convulsions, risk of thrombosis due to hematocrit rises.