Cyanocobalamin
Synonyms :
Hydroxocobalamin, Mecobalamin, Vit B12, Vitamin B12
Mechanism :
The drug substance is the hydroxylated active form of vitamin B12 and is a large molecule in which a trivalent cobalt ion is coordinated in four positions by a tetrapyrrole ring.
Indication :
- Vitamin B deficiency
- Methylmalonic academia
- Cobalamin utilization disorders
- Homocystinuria-remethylation defects
Contraindications :
Do not give until diagnosis fully established and monitor plasma potassium during initial therapy.
Dosing :
RDA:
0-6 months: 0.4 mcg
7-12 months: 0.5 mcg
1-3 years: 0.9 mcg
4-8 years: 1.2 mcg
9-13 years: 1.8 mcg
>14 years: 2.4 mcg
Pernicious anaemia:
Start: 30-50 mcg SC/IM OD x14 days or give a total dose of 1000 mcg. Maintenance: 100 mcg IM/SC monthly.
Vitamin B12 deficiency: IM/SC
0.2 mcg/kg for 2 days, followed by 1000 mcg/day for the next 2-7 days, this is then followed by 100 mcg/day for 2-7 days, then 100 mcg/week for 1 month. Maintenance dose: 100 mcg IM/SC monthly.
Adverse Effect :
Arthralgia, itching, chills, fever, hot flushes, headache, nausea, vomiting, dizziness and malaise.
Interaction :
No known interactions found.
Hepatic Dose :
No dosage adjustments are recommended.