Treatment of hypertension (HTN) in children, particularly very young children, may be difficult because few agents are available that can be dosed accurately in small patients. We have been prospectively evaluating the effectiveness of isradipine (IS) as an antihypertensive agent in children. A stable liquid preparation of this drug that allows for precise dose adjustments has been formulated by the University of Michigan Hospitals pharmacy and has been in use at our center for over 3 years. 39 children with HTN, aged 2.7 months - 16.5 years (mean age 66 months) were treated with IS. Etiology of HTN included renal transplant (12), liver transplant (13), glomerular disease (7), steroid-induced (4), and essential HTN (3). Approximately three-fourths were treated with IS suspension, the remainder with IS capsules. IS was effective as a single agent in 50% of patients treated. The average IS dose received was 0.39±0.16 mg/kg/day, range 0.15-0.9 mg/kg/day. Dosing interval was TID-QID for patients receiving liquid IS and BID-TID in patients receiving IS capsules. Mean systolic blood pressure(BP) fell from 124.3±9 mmHg to 116.3±11 mmHg (P<0.05), and mean diastolic BP fell from 74.4±13 mmHg to 69.4±10 mmHg (P=NS) with IS treatment. Side effects were mild and consisted primarily of tachycardia and flushing. No patient required discontinuation of IS.

We conclude that IS offers safe and effective control of HTN in children. Use of a liquid IS preparation allows precise dosing even in small infants.