What should I do if my toenails turn black?

Blackened toenails can be treated with oral antifungal medications, such as bifonazole, ketoconazole, amorolfine topical solution, and terbinafine. Blackening of the toenails is often caused by fungal infection; in severe cases, additional symptoms may include yellowing of the nail, onycholysis (separation of the nail from the nail bed), nail thickening, and nail hypertrophy. In daily life, ensure adequate rest and change shoes and socks regularly.