6th June 2025

Hypertrichosis

Hypertrichosis is defined as excessive hair growth anywhere on the body in either males or females. It is important to distinguish hypertrichosis from hirsutism, which is a term reserved for females who grow an excessive number of terminal hairs in androgen-dependent sites. Hypertrichosis can be either congenital (present at birth) or acquired later in life.

Two methods of classification are used for hypertrichosis. One divides them into either generalised versus localised hypertrichosis, while the other divides them into congenital versus acquired.

Definitions of Hypertrichosis

Congenital: Congenital forms of hypertrichosis are caused by genetic mutations, and are extremely rare, unlike acquired forms. Congenital hypertrichosis is always present at birth.

Acquired: Acquired hypertrichosis appears after birth. The multiple causes include the side effects of drugs, associations with cancer, and possible links with eating disorders. Acquired forms can usually be reduced with various treatments. Drugs associated with acquired generalised hypertrichosis include; Antibiotics such as streptomycin, Anti-inflammatory drugs such as benoxaprofen and corticosteroids, Vasodilators (diazoxide, minoxidil, prostaglandin E1), Diuretics (acetazolamide), Anticonvulsants (phenytoin), Immunosuppressives (cyclosporine, mycophenolate mofetil), Psoralens (methoxypsoralen, trimethylpsoralen), Antiseptic agents (hexachlorobenzene), Chelators (penicillamine), Interferon-alpha, Fenoterol and EGFR inhibitors (cetuximab, panitumumab, erlotinib, gefitinib).

There is no treatment for the underlying cause of hypertrichosis, but the symptoms may be managed with hair removal methods, such as shaving, waxing, epilation, or electrolysis – the chosen method is guided by the patient’s preference.