About Herbs

Bottom Line: Some studies suggest biotin may help to strengthen brittle nails and alleviate peripheral neuropathy (a disorder of the peripheral nerves) in diabetics. More studies are needed to confirm such effects.

Biotin is an important coenzyme involved in carbohydrate (sugar) and lipid (fat) metabolism. It is synthesized in the intestines and is commonly found in a variety of foods. Consuming large amounts of egg whites or taking anticonvulsant (antiepileptic) drugs may lead to biotin deficiency, although this is rare. Patients with diabetes may have a greater chance of being biotin deficient. However, biotin supplementation may weaken the activity of immune signals (i.e., interleukins and interferons) and reduce the number of white blood cells.

Seborrheic dermatitis
A small number of infants with seborrheic dermatitis were given 2 mg twice per day of biotin or a placebo. After three weeks the patients crossed over to the other treatment arm. Qualitative and quantitative changes were measured and no significant difference was found between treatment with biotin and placebo.

Brittle nails
Fourty-four patients with dry, splitting nails who were offered biotin therapy (2,500 micrograms/day from 1.5 to 7 months) were surveyed after completing their treatment. Of the patients who responded to the survey sixty-three percent reported improvement from the treatment. One patient reported gastrointestinal adverse effects. Further randomized trials are needed to confirm these results.

This product is regulated by the FDA as a dietary supplement. Unlike approved drugs, supplements are not required to be manufactured under specific standardized conditions.

The product may not contain the labeled amount or may be contaminated. In addition, it may not have been tested for safety or effectiveness.

Gastrointestinal complaints

One woman who took biotin along with Vitamin B₅ had a serious side effect, eosinophilic pleuropericardial effusion (inflammation and filling of the lining around the heart and lungs with fluid).

Cis-hexahydro-2-oxo-1H-thieno[3,4-d]-imidazole-4-valeric acid

Vitamin H, coenzyme R, D-Biotin, W Factor

An important coenzyme in carbohydrate and lipid metabolism, biotin has been claimed to treat brittle finger nails, acne, seborrhoeic dermatitis, hair fragility, and alopecia. Infants who died from sudden infant death syndrome (SIDS) were found to have significantly lower levels of biotin in their livers; however, evidence that biotin deficiency contributes to SIDS is lacking ⁽¹⁾. A small randomized controlled trial showed biotin to be no more effective than placebo in the treatment of seborrheic dermatitis in infants ⁽²⁾. One small retrospective study found that biotin supplementation is effective in strengthening brittle nails ⁽³⁾. Preliminary data suggests biotin may have beneficial effects in patients with severe diabetic peripheral neuropathy ⁽⁴⁾, and in combination with chromium, it may be effective as an adjunct therapy to improve glycemic control in patients with type 2 diabetes ⁽⁵⁾. Adverse effects are rare but a case of eosinophilic pleuropericardial effusion was reported in a woman taking biotin and pantothenic acid (i.e., vitamin B ₅) concomitantly ⁽⁶⁾.

Liver, kidney, eggs, soya beans, peanuts, wholegrain cereals, and dairy products ⁽¹⁾.

In the body, biotin is an essential part of carbohydrate and lipid metabolism by transporting carboxyl units and fixing carbon dioxide. Biotin is commonly found in a wide variety of foods. It is converted into the active form by an enzyme, biotinidase. Biotin is also synthesized in the intestine by bacteria. Patients who are deficient in biotinidase or who have malabsorption syndrome may develop biotin deficiency. Although biotin deficiency is rare, symptoms include anorexia, nausea, vomiting, dermatitis, somnolence, seizures, ataxia, and increase in serum cholesterol levels and bile pigments ⁽¹⁾. Biotin may also be deficient, inactive, or unavailable in patients with diabetes. Therefore, it is suggested that biotin supplementation may be effective against diabetic peripheral neuropathy ⁽⁴⁾; in neurons, biotin induces microtubule formation ⁽⁷⁾ and biotin deficiency slows myelination ⁽⁸⁾. However, biotin supplementation may reduce the activity of interleukins and interferons and reduce the number of leukocytes ⁽⁹⁾.

Absorption
Biotin is rapidly absorbed from the gastrointestinal tract through facilitated transport and passive diffusion. Absorption is greatest in the jejunum ⁽¹⁾. Certain anticonvulsant drugs inhibit biotin transport in the human intestine by competitively binding with the human brush border membrane vesicles ⁽¹⁰⁾.

Distribution
Biotin binds to plasma proteins ⁽¹⁾.

Excretion
Excess biotin is excreted via urine. It also appears in breast milk ⁽¹⁾.

Reported (Oral): One case of eosinophilic pleuropericardial effusion was reported in a woman using biotin and pantothenic acid (vitamin B₅) concomitantly ⁽⁶⁾.

Long term use of certain anticonvulsant drugs may accelerate biotin catabolism which theoretically could cause biotin deficiency ⁽¹¹⁾.