Role of hematinics on medical diseases .pptx

definiton, pharmacokinetics and role in different types of anaemia

1. Hematinics Hematinics are the compounds or nutrients required in the formation of blood (hematopoiesis) and are used for the treatment of anaemia . Major hematinics are: • Iron • Vitamin B 12 • Folic acid

2. Anaemia Anaemia is a condition in which the number of red blood cells or the haemoglobin concentration within them is lower than normal . Causes of anaemia : Blood Loss (acute or chronic) Eg . trauma, haemorrhage Decrease formation of RBC deficiency of essential factors such as Iron(Iron deficiency anaemia ), vitamin B12 ( pernicious anaemia ), folic acid (megaloblastic anaemia )

3. Anaemia Bone marrow depression eg : Aplastic anaemia erythropoetin deficiency eg : CKD Increase destruction of RBC- in haemolytic anaemia Increased demand as in growing children, child bearing, lactating women

4. Iron Iron is essential for the production of haemoglobin Daily requirement Adult male 0.5 -1 mg Adult female 1-2 mg Pregnancy 3-5 mg

5. Iron Dietary sources Rich: Liver, egg yolk, dry fruits Others: meat, chicken, fish, banana, milk and milk product, root vegetables Total body iron 2.5 to 5 gm Distribution of body iron Hb - 62% Store as Ferritin and haemosiderrin 25%

6. Iron Myoglobin (in muscle) 7% Enzymes (cytochromes) 6% Iron is stored in our body in ferric form in combination with large protein apoferritin Fe 3+ + Apoferritin Ferritin aggregates Haemosiderrin

7. Pharmacokinetics of Iron

8. Pharmacokinetics of Iron Absorption Iron is normally absorbed in the duodenum and proximal jejunum Dietary Iron is ingested in the form of heme or inorganic iron Heme is directly absorbed into the mucosal cells of intestine and inorganic iron converted to ferrous form (Fe ++ ) and then absorbed.

9. Factors influencing iron absorption Increase absorption • Ascorbic acid ( vit C) • Amino acids • Meat • Increased gastric acidity Decrease absorption • Antacids • Phosphates • Phytates (grains, beans, nuts etc.) • Tetracyclines • Presence of food in stomach

10. Pharmacokinetics of Iron Transport transported with the help of a glycoprotein transferrin. The transferrin-iron complex enters maturing erythroid cells by a specific receptor mechanism. Storage Iron is stored in RE cells ( in liver, spleen and bone marrow) as ferritin and hemosiderin.

11. Pharmacokinetics of Iron Excretion 0.5-1 mg of iron is excreted daily Mainly excreted through faces, little in urine and sweat.

12. Iron Preparations Iron is available both in oral and parenteral forms. Oral route is preferred. Indications For treatment • Iron deficiency anemia • Pregnancy • Blood loss • Poor iron absorption from gut For prophylaxis • Iron deficiency anemia • Pregnancy • Lactation • Chronic illness

13. Oral Iron Preparations Preparations Ferrous sulphate Ferrous fumarate Ferrous gluconate Ferrous succinate Adverse effects of Oral Iron Nausea Vomiting Metallic taste Constipation Epigastric pain Black stool

14. Parenteral iron preparations Indication When oral iron is not tolerated Failure of absorption-as in malabsorption, chronic bowel disease Non-compliance to oral iron Severe deficiency with bleeding Post gastrectomy patients Preparations Iron dextran - IV/IM Ferrous sucrose – IM Ferric carboxymaltose Iron-sorbitol-citric acid complex- only IM

15. Parenteral iron preparations Adverse effects Local : • Pain at the site of injection • Pigmentation of the skin • Abscess at the site of injection Systemic : • Fever • Headache • Nausea, vomiting • Joints pain • Enlargement of lymph node • Palpitation • Difficulty in breathing • Anaphylaxis (rarely)

16. Acute iron poisoning Overdose of iron can cause toxicity in body and known as acute iron poisoning. Most commonly occurs in infants and children 1-2 gm can be lethal Symptoms- vomiting , abdominal pain, diarrhea, drowsiness, acidosis , dehydration , cardiovascular collapse, coma Treatment- Gastric lavage with sodium bicarbonate Antidote- Desferoxamine (prevent iron absorption)

17. Vitamin B 12 2 compounds Cyanocobalamine Hydroxocobalamine They can be synthesized by microorganism Essential for DNA synthesis and RBC maturation. Dietary sources • Liver, fish, egg yolk, meat, cheese and pulses Daily requirement • Adults 1-3 μ g • Pregnancy and lactation 3-5 μ g

18. Vitamin B 12 Deficiency occurs due to- Destruction of parietal cells cause inability to absorb Chronic gastritis (gastric mucosal cell damage) Increased demand (during pregnancy)

19. Vitamin B 12 Pharmacokinetics Vitamin B 12 is absorbed in the intestine with the help of intrinsic factor, a protein secreted by the stomach. It is carried in the plasma by B 12 -binding proteins called transcobalamine and is stored in the liver up to 3 years and to erythropoietic cells to convert methy ltetrahydrofolic acid to tetrahydrofolic acid which helps in DNA synthesis. Excreted through bile

20. Vitamin B 12 Preparations Cyanocobalamin- may be given IM or deep SC Hydroxocobalamine Multivitamin preparations – oral form Indications Prophylaxis and treatment of • Megaloblastic anemia • Pernicious anemia • Intestinal malabsorption • B 12 neuropathies like subacute combined degeneration respond to vitamin B 12

21. Folic Acid Folic acid ( pteroylglutamic acid) is compose of pteridine , p- aminobenzoic acid and glutamic acid Essential for DNA synthesis and RBC maturation Dietary source: • Egg, Green vegetables, liver, yeast, milk Daily requirement • Adults 50-200 μ g • Pregnancy and lactation 300-400 μ g

22. Folic Acid Pharmacokinetics Absorption takes place in the proximal jejunum and is transported in the blood by active and passive transport , and is stored in the liver and other tissues Folates are excreted through urine and stool Low body storage and high daily requirement

23. Folic Acid Indications Megaloblastic anemia - Folic acid 2-5 mg/day is given orally along with vitamin B12. • Malabsorption syndrome - Folic acid is given IM. • Prophylactically in pregnancy, lactation,infancy - 500 mg daily orally

24. Erythropoietin Hormone that is glycoprotein in nature Stimulates RBC production Uses Treatment of anemia in chronic renal failure bone marrow disorders Malignancies Chronic inflammation & anemia associated with AIDS.