Biotin (Vitamin B7, Vitamin H) is a water-soluble B-complex vitamin that acts as an essential coenzyme for five carboxylase enzymes involved in critical metabolic pathways, including gluconeogenesis, fatty acid synthesis, and amino acid catabolism. A 5mg dose is a high-dose supplement, significantly exceeding the Recommended Dietary Allowance (RDA), primarily used for therapeutic purposes in managing biotin deficiency and specific dermatological/neurological conditions.
Adult: For deficiency: 5mg orally once daily. For maintenance/general supplementation: 30-100 mcg daily. Therapeutic use for hair/nails: 2.5-5mg once daily.
Note: Administer orally with or without food. Taking with food may reduce potential for mild gastrointestinal upset. Tablet should be swallowed whole with a glass of water. Consistent daily intake is recommended.
Biotin serves as an essential covalently bound coenzyme (prosthetic group) for five mammalian carboxylases: 1) Acetyl-CoA carboxylase (fatty acid synthesis), 2) Pyruvate carboxylase (gluconeogenesis), 3) Methylcrotonyl-CoA carboxylase (leucine catabolism), 4) Propionyl-CoA carboxylase (metabolism of odd-chain fatty acids, isoleucine, valine, methionine, threonine), and 5) Geranoyl-CoA carboxylase. These enzymes catalyze the ATP-dependent transfer of bicarbonate to their substrates, crucial for intermediary metabolism.
Pregnancy: Category A (US FDA). Considered safe. Required for embryonic growth. The 5mg dose is significantly above the RDA for pregnancy (30-35 mcg). Use should be under medical supervision if taken at this high dose, though no teratogenic risk is known.
Driving: No effect on driving ability.
| Anticonvulsants (Phenytoin, Carbamazepine, Primidone) | May increase biotin catabolism/excretion, potentially lowering biotin levels. | Moderate |
| Long-term Antibiotic Therapy | May reduce intestinal bacterial synthesis of biotin. | Mild |
| Isotretinoin | May reduce biotinidase activity, potentially increasing biotin requirements. | Mild |
| Pantothenic Acid (Vitamin B5) in very high doses | Theoretical competition for intestinal and cellular absorption via the SMVT transporter. | Mild |
Same composition (Biotin (5mg)), different brands: