Haematinics

Iron Deficiency Anaemia (IDA) (=Sideropenic anaemia) Folic Acid Vitamin B12 (Cobalamin) Erythropoietin

Sources

Low Medium High

Fruits

Vegetables

Fats

Red meats

Chicken

Eggs

Whole wheat

flour

Organ tissues

Fish

Green

vegetables

Tomatoes

Functions

Production of RBCs in bone marrow

Neural tube formation

Functions

Normal functioning of Brain & Nervous system

Formation of blood

Function (hormone )

Controls RBC production

Sources

Leafy green vegetables

Fish, Meat, Poultry

Whole grains

Iron Metabolism

Absorption in Duodenum & Jejunum (proximal)

Absorption ↑ when

• Iron stores ↓

• Iron requirements ↑

Absorbed better in Ferrous (Fe2+) – via active transport

Stored in

• Ferritin (mucosa)

• Transferrin (plasma)

Haemosiderin (alternative storage) = Ferritin + extra

Iron

Iron loss – 1mg/ day

• Urine

• Faeces

• Shed cells

• Menstruation – 20mg/ month

RBCs are destroyed by RES (reticuloendothelial system)

after 120 days – iron returned to Transferrin & Ferittin

Pharmacokinetics

Absorbed in small intestine (primarily Proximal)

Appears in plasma approx. 15-30 mins

Metabolised in liver

(7,8-dihydroFolic acid then to 5,6,7,8-tetrahydroFolic acid)

TetrahydroFolic acid derivates – distributed to all body

tissues (primarily stored in Liver)

Excreted in urine (small amounts in feces)

Excreted in milk of lactating mothers

Absorption & Distribution

Intrinsic Factor (IF) produced by cell in stomach

IF + B12

Form IF-B12 comple x, absorbed in intestines

Deficiency of IF

Cause abnormal formation of erythrocytes

(failure of B12 absorption)

Production

Endogenous erythropoietin produced by kidney

(response to anaemia, hypoxia)

Signal BM to produce more RBC

Hypochromic

Microcytic

Megaloblastic

anaemia

Large,

abnormal,

immature

erythrocytes

Pernicious Anaemia

(lack of gastric IF)

(autoimmune disease )

Abnormally large RBC

(macrocytes)

Abnormal WBC

(abnormal nuclei)

Causes

Excessive blood loss

Inadequate intake of iron

Women Men Children

Menstruation Blood loss Nutrition diet

Pregnancy Gastric ulcer

Neoplasm

Deficiency Causes

• Folate need ↑ (pregnancy, lactation)

• Intake ↓ (poor diet, alcoholics)

• Malabsorption syndromes

• Treatment with drugs – DHF (dihydrofolate)

reductase inhibitors (eg. Trimethoprim)

• Renal dialysis (Folate removed during dialysis)

• Liver disease (diminished hepatic storage Folate)

• Cancer, Leukaemia, Myeloproliferative disorders

Deficiency Causes

Failure of IF secretion

Absense of IF intestinal receptors

Gastrectomy (achlorhydria, lack of IF)

Malabsorption syndrome

Lack of B12 binding protein in plasma

(transcobalaimin II, α, β globulin)

↓ stomach acidity (inability to remove B12 from meat)

Liver disorders (interfere with storage of B12)

Failure to respond to erythropoietin

Concurrent iron deficiency (corrected with oral iron)

Clinical

Tissue hypoxaemia – easy fatiguability

Cardiopulmonary compe nsation – palpitation,

dyspnoea

Metaboolic consequences – O2 dissociation curve

change

Glossitis, Angular stomatitis, Brittle nails, Dysphagia

Pica (crave to eat non-food)

Clinical

Mild jaundice

Glossitis

Angular stomatitis

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Iron Deficiency Anaemia (IDA) (=Sideropenic anaemia) Folic Acid Vitamin B12 Erythropoietin

Iron Preparation

Oral Parenteral (IV, IM)

Corrects IDA as rapidly

as parenteral

Given only when oral

therapy failed

• Cannot take oral drugs

• Experience GIT

intolerance to oral

Should not be used

(affe ct absorption)

SR (sustained release)

EC (enteric-coated)

Types

Ferrous sulfate

Ferrous gluconate

Ferrous fumarate

Types

Iron Dextran (IM, IV)

Dextriferron (IV)

Saccharated iron oxide (IV)

Side Effects

Black stools

Nausea

Epigastric pain

Constipation

Diarrhoea

Side Effects

Local pain, tissue staining

Headache

Diarrhea, Nausea, Vomiting

Bronchospasm

Anaphylaxis (*test dose)

Death

Side effects are dose

dependent.

Overcome by

• ↓ Daily dose

• Taking after/ with

meals

“Z track” injection

Avoid local tissue staining

(brown discoloration)

Prevent escape of solution

from muscle tissue

Oral supplements

Megaloblastic anaemia

Folic acid deficiency

1mg dose sufficient to

Remove megaloblastic anaemia

Restore normal serum folate levels

Replenish body stores of folate

Cyanocobalamin (synthetic form of B12 )

Oral Parenteral

Pernicious anaemia can be

treated entirely

(1000 ug/ day)

Cyanocobalamin

Hydroxocobalamin

(↑ protein-bound)

(remain longer in blood)

Therapeutic uses (Treating anaemia)

Chronic Kidney Disease & Myelodysplasia

Cancer patients receiving chemotherapy & radiation

Critical illness (heart failure)

AIDS patient receiving zidovudine (AZT)

1° Bone Marrow

Side Effects

Allergic hypersensitivity (parenteral)

Side Effects

Itching, Rash

Mild diarrhoea

Peripheral vascular thrombosis, ↑ RBC production

Side Effects

Rapid ↑ Haematocrit & Hb

Hypertension, Thrombotic compli cations

Influenza-like symptoms

(can be reduced if IV injection given over 5 mins)

Allergic reaction (infrequent, mild)

Contraindications

Hypersensitivity to drug

Hemochromatosis/ Hemolytic anaemia

Anaphylatic-type reaction (parenteral)

Contraindications

Pernicious anaemia

Aneamis which B12 is deficient

Darbepoetin alfa

(long acting, synthetic form of erythropoietin)

Treatment of

Chronic renal failure (IV, subcutaneous injection)

Anaemia in cancer patients undergoing chemotherapy

Risks of use

Cardiovascular problems

Cardiac arrest

Arrhythmia

Hypertension

Hypertensive encephalopathy

Congestive heart failure

Vascular thrombosis/ ischemia

Myocardial infarction

Edema

Interactions

(form insol uble complex, ↓ absorption)

Tetracycline (antibiotic)

Methyldopa

Levodopa

Bisphosphonates

Quinolones

Calcium (food)

Absorption (Better at ↓ pH) Decreased when taking

Antacids, Phosphates, Tannins (from tea)

Interactions

Phenytoin (antagonize anticonvulsant action)

Epilepsy patient require ↑ dose of Phenytoin if Folic Acid

given

Toxicity

Acute (children common) Chronic

Necrotising gastroenteritis = Haemosiderosis

= Haemochromatosis Nausea, Vomiting,

Diarrhoea

Acidosis, Cyanosis,

Circulatory collapse

Excess deposits in Heart,

Liver, Pancreas

(organ failure) Gastric scarring

Pyloric stenosis

Treatment

Induce vomiting, lavage

(phosphate, carbonates)

Hasten evacuation

(catharsis/ purging)

Sodium bicarbonate

Desferrioxamine/

deferoxamine

Treatment

Intermittent phelebotomy

Desferrioxamine

(if involve iron overload –

ocular haemosiderosis,

haemochromatosis)

Folinic Acid (Not the same as Folic Acid)

(= leucovorin)(Calcium folinate/ Leucovorin calcium)

• Treat folate deficiency megaloblastic anaemia

• Adjuvant – cancer chemotherapy (involve

Methotrexate) (rescue/ reverse toxic effects of

methotrexate)

• Used synergistically with 5-fluorouracil

(chemotherapy agent)

Supplements

Supplement in processed foods

Vitamin pill form (multi-vitamins)

Mode

Liquid

Transdermal patch

Nasal spray

Injection

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