Cardiovascular responses of hyperactive children to methylphenidate
J. E. Ballard, R. A. Boileau, E. K. Sleator, B. H. Massey and R. L. Sprague
Heart rate, blood pressure, and oxygen consumption were measured in 27
hyperactive children during rest, exercise, and recovery, once taking
placebo and again taking methylphenidate hydrochloride. Half were measured
first taking the drug and half first taking the placebo. Twenty-three
matched controls were also measured twice to test for reproducibility of
results. Drug and placebo ECGs were recorded on 12 of the subjects. Oxygen
consumption did not change (P = .40), but heart rate (P = .001) and blood
pressure (P = .003) increased significantly with methylphenidate therapy.
There was a significant correlation between size of dose in milligrams per
kilogram and increase in heart rate (.38, P less than .05) and blood
pressure (.50, P less than .05 systolic) (.46, P less than .05 diastolic).
No evidence of the development of tolerance to these drug effects was found
in children who had been taking methylphenidate from two months to more
than a year. No ECG changes other than tachycardia were seen.
