Stuttering. The effect of treatment with D-amphetamine and a tranquilizing agent, trifluoperazine. A preliminary report on an uncontrolled study.

In an institution for the mentally retarded, an uncontrolled study was made on the effects of d-amphetamine, d-amphetamine followed by trifluoperazine, and of combined d-amphetamine and trifluoperazine on stuttering. Of 28 patients to whom d-amphetamine was given, 14 showed improvement after one month's treatment. Eight more showed improvement when trifluoperazine was given for one month to those who did not improve on d-amphetamine. In many cases, improvement was sustained at least six months after treatment was discontinued. Treatment with d-amphetamine was apparently more effective in patients with functional than with organic retardation.