Long Term Transdermal Clonidine Gets Under The Skin In the treatment of patients with mild to moderate essential hypertension

The long term antihypertensive efficacy of transdermal clonidine was assessed in an open study 23 patients with mild to moderate essential hypertension (diastolic BP 90-104mm Hg) received transdermal clonidine (delivering 0.1, 0.2 or 0.3mg daily) applied once a week for 2 years, following a 2-week transdermal placebo run-in. If BP was uncontrolled (diastolic BP ~ 90mm Hg or reduced by < 5mm Hg for patients with baseline diastolic BP 90-99mm Hg or < 10mm Hg for patients with baseline diastolic BP 100-104mm Hg) by clonidine monotherapy, chlorthalidone 25mg daily was given instead of, or in addition to, clonidine.

After dose titration, BP was controlled by clonidine alone in 14 patients and by combination therapy in 6 patients. Diastolic BP was reduced from 99 to 81 mm Hg (p < 0.01) in 11 patients who received clonidine monotherapy for 1 month after achieving BP control, but rose to 92mm Hg 1 month later. After 12 months of clonidine monotherapy (n = 8), diastolic BP was reduced from 100 to 87mm Hg (p < 0.05), and after 2 years (n = 4) diastolic BP had fallen from 99 to 84mm Hg (p < 0.05). Systolic BP was not significantly different from baseline after 12, 18 or 24 months of monotherapy. 14/20 patients whose BP was controlled by clonidine or combination therapy withdrew from the study because of severe skin reactions (n = 10) or non skin-related adverse effects (4). The most frequent of other adverse effects were fatigue, dry mouth and impotence.

The authors concluded that in those patients who do not develop skin reactions, transdermal clonidine is ' ... a safe and efficacious agent for short·term therapy' of mild to moderate essential hypertension. Horning JR. Zawada ET. Simmons JL. Williams L. McNulty R. Chesl 93 941·945. May 1988 103~

8 INPHARMA® 2 July 1988 0156-2703/ 88/ 0702-0008/ 0$01.00/ 0 © ADIS Press