Menadione

Skeltal formula

File:Menadione-3D-balls.png

Ball-and-stick model

Menadione is a synthetic chemical compound which holds significance in the realm of nutritional supplements due to its vitamin K activity. Structurally, it is an analog of 1,4-naphthoquinone with a specific methyl group positioned in the 2-location.

Terminology

Menadione has various names and classifications, including:

• Vitamin K3: Even though it is often referred to as vitamin K3, it is vital to note that naphthoquinone derivatives lacking the side chain in the 3-position do not uphold all the roles characteristic of K vitamins.
• Provitamin: Menadione acts as a vitamin precursor to K2. It undergoes alkylation to produce menaquinones (MK-n, where n ranges from 1 to 13; these are K2 vitamers). Hence, classifying menadione as a provitamin is more accurate.
• It also goes by the name menaphthone.

Uses

Menadione, despite being a precursor to several vitamin K types, is sparingly used as a nutritional supplement in developed nations due to:

• Human Consumption: In some countries with vast low-income populations, pharmaceutical strength menadione is available. Yet, high dosages are linked to adverse events such as hemolytic anemia due to G6PD deficiency, potential neonatal brain or liver damage, or even neonatal death in sporadic incidents. The U.S. Food and Drug Administration (FDA) prohibits menadione supplements in the United States because of these toxicities.
• Livestock and Pets: Menadione, in low doses, is utilized as a cost-effective micronutrient for livestock. It is also present in pet foods in certain developed nations as a vitamin K source. These dosages have shown no toxicity in livestock or pets.
• Medical Use: Outside the US, menadione finds application in treating Hypoprothrombinemia.

Experimental Research

• Cancer Treatment: Recent studies are delving into the combined use of menadione and vitamin C as a potential treatment methodology for prostate cancer.
• Topical Lotion: A topical lotion containing menadione has been developed aiming to mitigate the side effects related to epidermal growth factor receptor inhibitors. The lotion proves beneficial in averting skin toxicities stemming from protein kinase inhibition by drugs like erlotinib (Tarceva) and cetuximab (Erbitux).

See Also

• Vitamin K
• Chemical compound
• U.S. Food and Drug Administration

Vitamins A Vitamin A B Biotin Vitamin B1 (see Thiamin) Vitamin B12 Vitamin B6 C Calcium Choline Chromium Copper Vitamin C D Vitamin D

E Energy Drinks Exercise and Athletic Performance Vitamin E F Fluoride Folate I Iodine Iron K Vitamin K

M Magnesium Multivitamin/mineral Supplements N Niacin P Pantothenic Acid Phosphorus Potassium Primary Mitochondrial Disorders R Riboflavin

S Selenium T Thiamin V Vitamin A Vitamin B1 (see Thiamin) Vitamin B12 Vitamin B6 Vitamin C Vitamin D Vitamin E Vitamin K Z Zinc