Vit B12 Pharmacology

Vit B12

About Vit B12
N/A
Mechanism of Action of Vit B12
Vitamin B12 is an essential constituent for growth, cell reproduction, hematopoiesis, and nucleoprotein and myelin synthesis. Vitamin B12 is converted in to coenzyme B12 in the tissues which is essential for conversion of methyl-malonate to succinate and synthesis of methionine from homocystine. It is also associated with fat and carbohydrate metabolism and protein synthesis. Cells characterized by rapid division such as epithelial cells, bone marrow, and myeloid cells appear to have greatest requirement of Cyanocobalamin.
Pharmacokinets of Vit B12
Absorption: Absorbed irregularly after oral administration and absorption depends on Ca and intrinsic factor. It is also administered subcutaneously and intramuscularly.
Distribution: Distributed in to liver, bone marrow, and other tissues. It crosses the placenta and appears in breast milk.
Metabolism: It is metabolized in liver.
Excretion: In normal dosage it is reabsorbed from bile and a minute portion is excreted through urine but the extra drug is excreted through urine.
Onset of Action for Vit B12
N/A
Duration of Action for Vit B12
N/A
Half Life of Vit B12
N/A
Side Effects of Vit B12
1. Anaphylaxis
2. Anaphylactoid reactions
3. Pain and burning sensation at injection site
4. Itching
5. Urticaria
6. Transient diarrhea
7. Peripheral vascular thrombosis
8. Pulmonary oedema
Contra-indications of Vit B12
1. Hypersensitivity to the drug
2. Leber`s disease
Special Precautions while taking Vit B12
1. Anemic patients with coexisting cardiac, pulmonary and hypertensive diseases.
Pregnancy Related Information
May be used
Old Age Related Information
May be used
Breast Feeding Related Information
May be used
Children Related Information
Use with caution
NEONATES : Use with caution
Indications for Vit B12
1. Vitamin B12 deficiency
2. Pernicious Anaemia
3. Peripheral neuropathy (diabetic, alcoholic, and drug induced)
Interactions for Vit B12
N/A
Typical Dosage for Vit B12
I.M., S.C.:
Pernicious Anaemia: 100mcg daily for 1 week followed by the same dose given on alternate days for 7 doses and then every 3 to 4days for another 3 weeks. This regimen should be followed by 100mcg monthly for life. Concurrently administer folic acid if required.
Vitamin B12 deficiency other than pernicious Anaemia: 30mcg daily for 5 to 10days depending up on the severity of the condition.
Maintenance dosage: 100 to 200mcg once monthly.
Children: 100mcg I.M. or S.C. over the course of 2 or more weeks.
Maintenance dosage: 60mcg monthly I.M. or S.C.
Schilling test flushing dose:
Adults and Children: 1000mcg I.M. in single dose
Recommended RDA (recommended dietary allowance) for Vitamin B12:
Infants up to 6months of age: 0.3mcg.
Children age 6 months to 1 year: 0.5mcg.
Children age 1 to 3: 0.7mcg.
Children age 4 to 6: 1mcg.
Children age 7 to 10: 1.4mcg.
Children age 11 to adult: 2mcg..
Pregnant women: 2.2mcg.
Breast feeding women: 2.6mcg.
Schedule of Vit B12
C
Storage Requirements for Vit B12
Store at room temperature range of 15 to 30 degree C.in a light resistant well closed container in a dry place.
Effects of Missed Dosage of Vit B12
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Vit B12
Not applicable. Even in large doses Vitamin B12 isn`t usually toxic.

Home Delivery for Vit B12 in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including vit b12.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for vit b12 and other medicines and health products. Home delivery services for vit b12 may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take vit b12 only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for vit b12 before they complete the sale. You can get this information while placing the order for vit b12 with the pharmacy.

Vit B12 is a generic medicine name and there are several brands available for it. Some of the brands for vit b12 might be better known than vit b12 itself. If the pharmacy that's willing to deliver medicines to your home doesn't have vit b12 in stock, you can ask for one of the branded alternatives for vit b12.