Specific nail involvement occurs in about 10% of patients with lichen planus and
permanent damage of at least one nail occurs in approximately 4% of patients. However,
if lichen planus is correctly diagnosed and treated, permanent damage to the nail unit is
rare, even where there is diffuse involvement of the nail matrix.
Systemic steroids are effective in treating nail lichen planus: intramuscular
triamcinolone acetonide 0.5 mg/kg every month for 2–3 months usually produces
recovery of the nail abnormalities. Intralesional injections of triamcinolone acetonide
10mg/ml represent a possible, but painful, alternative when the disease is limited to a few
finger nails. Mild relapses are frequently observed, but recurrences are usually
responsive to therapy. Steroid treatment is not useful in pterygium, since the nail matrix
cannot be regenerated. Systemic retinoids at dosages suitable for psoriasis are a good
alternative.