MECO AND MECO-OD

Rx                MECO AND MECO-OD

COMPOSITION

MECO

Each tablet contains

Methylcobalamin        500mcg

MECO-OD

Each orange flavoured sublingual tablet contains

Methylcobalamin        1500mcg

DESCRIPTION

MECO and MECO-OD contain Methylcobalamin as the active ingredient. Methylcobalamin is one of the two co-enzyme forms of vitamin B₁₂ that acts as a cofactor in the enzyme methionine synthase which functions to transfer methyl groups for regeneration of methionine from homocystine. Methylcobalamin can be used by the body without extra metabolic conversions and is the preferred form for optimal uptake, assimilation, and use in the body.

Ø  C₆₃H₉₁CoN₁₃O₁₄P

PHARMACOLOGY

PHARMACODYNAMICS:

Methylcobalamin transfers its methyl group to homocystine yielding methionine which is then converted to S-adenosylmethionine, a major donor of methyl groups in transmethylation reactions, including synthesis of basic myelin proteins. Methylcobalamin promotes the repair of damaged nerves by the following action:

·   Methylcobalamin is closely involved in folate metabolism which is essential for the synthesis of purines and pyrimidines and therefore of DNA.

·   Promotes the conduction through the nerve cell bodies.

·   Improves excitability of nerve fibers thus improving neurotransmission.

·   Promotes the synthesis of lecithin, the main constituent of medullary sheath lipids and increases myelination of neurons.

PHARMACOKINETICS;

Methylcobalamin is utilized and absorbed more efficiently than cyanocobalamin to increase levels of one of the coenzyme forms of vitamin B12 following oral administration. The quantity

of cobalamin detected following a small oral dose of methylcobalamin is similar to the amount  following administration of cyanocobalamin; but significantly more cobalamin accumulates in

liver tissue following administration of methylcobalamin. Human urinary excretion of methylcobalamin is about one-third that of a similar dose of cyanocobalamin, indicating  substantially greater tissue retention.

Absorption: Vitamin B12 gets bind to intrinsic factor (IF) and form a complex. This IF-B12  complex is then absorbed in distal ileum. This absorption is done by a very specific receptor

mediated transport system.

Distribution: Vitamin B12 is distributed to different cells of the body upon binding to  transcobalamin II. It is stored in the liver in amount of 300-500 µg.

Elimination: Normally, very little amount is excreted through urine or feces but upon parenteral

administration large amount is found in urine.

Indications:

1.      Peripheral neuropathies like diabetic neuropathy, alcoholic neuropathy, drug induced neuropathy

2.      Dementia

3.      Bell’s palsy

4.      Post herpetic neuralgia

5.      Trigeminal neuralgia

6.      Parkinson’s disease

7.      Alzheimer’s disease

8.      Sciatica

9.      Brain ageing

10.  Sleep Disturbances

11.  Male infertility

12.  Carpal tunnel syndrome

13.  Vitamin B₁₂ deficiency

CONTRAINDICATIONS:

Hypersensitivity to any of the components of this product, Leber’s disease (inherited eye problem), tobacco amblyopia^* and B₁₂ deficiency without confirmed diagnosis.

PRECAUTIONS:

Regular monitoring of serum K⁺ is recommended during initial therapy as hypokalaemia can occur due to increased cellular K⁺ requirements when anemia corrects.

USE IN PREGNANCY AND LACTATION:

Not contraindicated

DRUG INTERACTIONS:

·        Neomycin, Aminosalicylic acid, H₂ receptor antagonists and Colchicine: Decreased GIT absorption.

·        Oral Contraceptives: Reduced serum concentration.

·        Tetracycline: Reduced absorption and efficacy of Methylcobalamin.

·        Metformin may decrease the absorption of methylcobalamin. This possible effect may be reversed with oral calcium supplement.

·        Colestipol may cause decreased absorption of methylcobalamin.

·        Para-amino salicylic  acid: chronic use of the anti-tuberculosis drug may decrease the absorption of methylcobalamin.

·        Potassium chloride: It has been reported that potassium chloride may decrease the absorption of methylcobalamin.

·        Proton Pump Inhibitor (lansoprazole, omeprazole, pantoprazole, rabeprazole); Chronic use of proton pump inhibitors may result in decreased absorption, naturally found in food sources.

·        Cholestyramine: cholestyramine may decrease the enterohepatic reabsorption of methylcobalamin.

ADVERSE EFFECTS:

Anaphylactic reaction: Anaphylactic reaction such as decrease in blood pressure or dyspnea may occur. Patient should be monitored after admi9nistration of dose.

DOSAGE AND ADMINISTRATION:

MECO-OD: 1 Tablet daily to be allowed to dissolve under the tongue.

MECO       :  1 Tablet three times a day.

The dosage may be adjusted depending on the patient’s age and symptoms.