Graying hair is a cardinal sign of aging, typically beginning in a person’s fourth or fifth decade. Nutritional deficiencies, including low intake of protein, vitamin B12, iron, and copper, can contribute to premature graying. However, a recent review found that some medications may promote gray hair re-pigmentation.

Researchers reviewed 27 studies and case reports of medication-induced gray hair re-pigmentation, totaling 133 patients. They categorized the various drugs as anti-inflammatories, stimulators of melanogenesis (the production of melanin, the pigment responsible for hair, skin, and eye color), vitamins, medications that accumulate in tissues, and those with an undetermined mechanism. Then, they ranked the quality of the evidence for each study or report.

They found that medications that reduce inflammation or stimulate melanogenesis can promote diffuse re-pigmentation of gray hair. They also found that vitamin B complex supplementation may contribute to the darkening of gray hair, but they cautioned that evidence supporting this finding was weak.

These findings suggest that certain medications induce gray hair re-pigmentation. Although these drugs aren’t presently recommended for treating gray hair, their mechanisms provide insights into potential targets for future medications aimed at hair re-pigmentation.