Methyl nicotinate

Absorption

The presence of methyl group facilitates the penetration of methyl nicotinate through the skin with good lipophilicity, allowing rapid absorption following topical administration . In vitro, about 80-90% of the polar compounds methyl nicotinate rapidly penetrated the skin . It was demonstrated in excised skin of hairless mice that methyl nicotinate can effectively bypass the stratum corneum layer of the skin . In humans, nicotinic acid and nicotinamide were shown to be rapidly absorbed from the stomach and intestine via a sodium carrier-mediated mechanism at low concentrations .

Toxicity

The acute subcutaneous LD50 of structurally-related nicotinamide and nicotinic acid in rats were 1.68 and 5.0 g/kg bw, respectively . In humans, oral ingestion of 3-9 g of nicotinic acid per day resulted in "niacin hepatitis", gout, and impaired glucose intolerance within a short period of time .

Description

Methyl nicotinate is the methyl ester of Niacin that is used as an active ingredient as a rubefacient in over-the-counter topical preparations indicated for muscle and joint pain. The action of methyl nicotinate as a rubefacient is thought to involve peripheral vasodilation. For veterinary purposes, methyl nicotinate is used to treat respiratory diseases, vascular disorders, rheumatoid arthritis, and muscle and joint pains.

Chemical properties

Methyl nicotinate is white to brownish crystals or crystalline powder and has a fresh, caramellic, nutty and mild tobacco odor.

The Uses of Methyl nicotinate

Methyl nicotinate is used as an active ingredient, a rubefacient and counter-irritant in over-the-counter topical preparations indicated for the temporary relief of aches and pains in muscles,tendons, and joints. Methyl nicotinate can be found in in guava fruit, papaya, strawberry, soursop(Annona muricata), beer, grape brandy, coffee, roasted filbert, roasted peanut and Bourbon vanilla.

Indications

Indicated for the temporary relief of aches and pains in muscles, tendons, and joints.

Preparation

Methyl nicotinate was prepared by esterification of nicotinic acid by refluxing with methanol in the presence of concentrated sulphuric acid, esterification product obtained was extracted into organic solvent (chloroform) after neutralization of the reaction mixture with 10% sodium bicarbonate.
Synthesis and antinociceptive activity of methyl nicotinate
DOI:10.4314/jpb.v12i1.8

Pharmacokinetics

Following topical administration, methyl nicotinate acts as a peripheral vasodilator to enhance local blood flow at the site of application. It induced vasodilation of the peripheral blood capillaries which are located in the dermal papillae of upper dermis layers adjacent to the epidermis–dermis junction . During tissue penetration at the dermis, methyl nicotinate is hydrolyzed to nicotinic acid . In human volunteers, topical administration of methyl nicotinate caused vasodilation-induced generalized cutaneous erythema .

Side Effects

There is presently no side effect information available for Methyl nicotinate(MN) itself. a few patients who applied a medicated topical preparation containing MN (and other components) suffered adverse reactions including faintness, nausea, pain and skin rashes.

Metabolism

Methyl nicotinate undergoes ester hydrolysis to form nicotinic acid and methanol . The hydrolysis is thought to be mediated by nonspecific α-naphthylacetate-esterase at the dermis layer of the skin .