A clinical trial of seventy-five patients suffering from depressive illness and treated with maprotiline (Ludiomil) is reported. Twenty-eight patients were given a single nightly dose of 75 mg and twenty-six patients were treated with 25 mg three times daily. Twenty-one patients withdrew from the trial. It was found that those patients on the nocte regime made greater improvement than those on the divided dosage. Sleep disturbances and mood swings were significantly improved on the nocte dosage. Both regimes were equally well tolerated. Special care was taken in recording any adverse drug effects in order to distinguish these from pre-existing symptoms of the illness.