Anaemia is a pathological condition arising as a result of low level of haemoglobin in the body. Reduction of haemoglobin impairs oxygen transport to the tissues – the basis of the clinical features of anaemia.
Anaemia can be classified according cause and mechanism of development
• Four major groups care distinguished:
+ Hemorrhagic anemia – develops due to various forms of bleeding (trauma, excessive menses, bleeding associated with pregnancy and birth giving, and parasitic infestations such as hookworms and schistosomiasis).
+ Haemolytic anemia – due to massive destruction of red blood cells as occurs in malaria and sickle cell disease.
+ Hypoplastic/Aplastic anemia – due to failure of bone marrow to produce sufficient red blood cells. Bone marrow depression can be caused by diseases (autoimmune, viral infection), radiation and chemotherapy and intake of some drugs (anti-inflammatory, antibiotics).
+ Nutritional anemia – due to deficiency of the nutrients needed for the synthesis of red blood cells: iron, folic acid and vitamin B12. Nutritional anemia are
o Iron deficiency anemia
o Folic acid deficiency anemia
o Vitamin B 12 deficiency anemia
• Anemia affects all population groups but children aged below five years and pregnant women are the most vulnerable.
Symptoms of Anemia
• Decreased oxygenation –Exertional dyspnea
–Dyspnea at rest
• Decreased volume –Fatigue
–Syncope (transient, self-limited loss of consciousness due to hypotension that is followed by spontaneous recovery.)
Prevention of Anaemia
Consumption of iron and vitamin rich foods. Iron in foods of animal origin (haem iron) is more easily absorbed compared with iron in foods of plant origin (which is mostly non-haem iron). Vitamin C enhances absorption of iron while tea and coffee inhibits iron absorption.
Prevention and treatment of anaemia related diseases (malaria, worm infestation, other infections)
• Iron and folic acid supplementation to the most at risk groups – children, pregnant women, sickle cell patients
• Use of micronutrients fortified foods (iron and folic acid included)
Treatment of Anaemia
Most appropriate oral iron therapy is use of a tablet containing ferrous salts+ Ferrous sulfate+ Ferrous fumarate+ Ferrous gluconate
Parenteral iron therapy for iron deficiency anemia
• Iron dextran injection
• Iron sucrose injection
• Sodium ferric gluconate complex injection.
Reserve parenteral iron for
• patients who are unable to absorb oral iron
• Rarely given when patients cannot tolerate oral form
• If iron loss exceeds oral iron replacement
• Patients with inflammatory bowel disease,as the ferrous sulfate preparations may aggravate the
Other ant anemic drugs
• Folic acid; used in management of anaemia and neuro tube defect.
- Hydroxocobalamin is also known as vitamin B12, it is used in management of megaloblastic anaemia.
• Ferrous sulphate is not contra-indicated to specific group of individual but should be given with care to those people with peptic ulcers.
• Folic acid is not contra-indicated to specific group of individual but should never be given alone for pernicious anaemia and other vitamin B12 deficiency states since it may precipitate subacute combined degeneration of the spinal cord.
• Hydroxocobalamin is not contra-indicated to specific group of individual but should not be given before diagnosis fully established.
• Iron dextran Injection is contra-indicated to those with history of allergic disorders including asthma and eczema, infection, active rheumatoid arthritis, severe hepatic impairment and acute renal failure.
Dose, Dosage and Course of treatment
• Dose prophylactic, 1 tablet (200mg) daily; therapeutic, 1 tablet 2–3 times daily until signs and symptoms disappear.
• Folate-deficient megaloblastic anaemia, by mouth, adult and child over 1 year, 5 mg daily for 4 months (until term in pregnant women); up to 15 mg daily may be required in malabsorption states;
• Children under 1 year, 500 micrograms/kg daily (max. 5 mg) for up to 4 months; up to 10 mg daily may be required in malabsorption states
• By mouth, vitamin B12 deficiency of dietary origin, 50–150 micrograms daily taken between meals children 50–105 micrograms daily in 1–3 divided doses.
• By intramuscular injection, initially 1 mg repeated 10 times at intervals of 2–3 days, maintenance 1 mg every month.
Iron dextran Injection
• By deep intramuscular injection into the gluteal muscle or by slow intravenous injection or by intravenous infusion, 50mg/mL, 2ml ample or calculated according to bodyweight and iron deficit.
• The product is not recommended to children under 14 years.
Side Effects and Adverse Effects
Oral Iron Therapy:
• Gastro-intestinal irritation
• Nausea and epigastric pain
• constipation, black stools,
• Oral iron, particularly modified-release preparations, can exacerbate diarrhea
Not common, rarely gastro-intestinal disturbances
• Nausea, headache, dizziness and fever
• Hypersensitivity reactions (including rash and pruritus) may occur.
• Injection-site reactions
• Thrombocytosis (An increase in the number of platelets in the circulating blood.)
• Chromaturia (abnormal coloration of the urine.)
Parenteral iron therapy side effects:
Not common, they may include;
• Nausea, vomiting and abdominal pain
• Flushing, dyspnoea and anaphylactic reactions
• Numbness, cramps and blurred Vision
• Pruritus, and rash;
Interactions and Precautions
• Vitamin C can facilitate iron absorption
• Absorption of Ferrous sulphate is reduced by oral magnesium salts, calcium salts and zinc.
• Ferrous sulphate reduces absorption of ciprofloxacin and other fluoroquinolones, levodopa, mycophenolates, Penicillamine, bisphosphonates and levothyroxines
• Folic acid; usually does not interact with any specific group of drugs or any individual drug.
• Hydroxocobalamin; usually does not interact with any specific group of drugs or any individual drug.
• Iron dextran Injection; usually does not interact with any specific group of drugs or any individual drug.