The effects of methylphenidate and haloperidol on the heart rate and blood pressure of hyperactive children with special reference to time of action.

Twelve hyperactive-aggressive children were given single acute doses of placebo, methylphenidate (0.3 mg/kg) and haloperidol (0.035 mg/kg) on three separate occasions in a double blind crossover design with drug order randomized across subjects. Resting heart rates and systolic and diastolic blood pressures were obtained at nine intervals up to 7 hrs and electrocardiograms at 150 min after ingestion. Methylphenidate caused a small trend toward an increment in heart rate and a significant increment in blood pressure, while the changes with haloperidol were minimal. There were no EKG changes. Changes in heart rate were of a minimal nature as compared with those occurring with digestion which tended to obscure drug effects.