Thirty-five patients presenting with phthiriasis palpebrarum were all treated with a regimen of 1% yellow oxide of mercury ointment four times daily for 14 days. At the conclusion of treatment there was complete resolution of the signs and symptoms of the disease. No side effects due to the treatment were reported or detected. We have shown that 1% mercuric oxide ointment is both a safe and effective treatment for phthiriasis palpebrarum. We recommend it as the treatment of choice.