Is Antihypertensive Therapy Getting Under Your Skin? Transdermal clonidine provides constant BP control and improved tolerability

25 patients (mean age 52 years) with mild to moderate essential hypertension (seated diastolic BP 95-120mm Hg during diuretic monotherapy) received a diuretic + oral clonidine for a mean period of 64 months Oral clonidine was then replaced with transdermal clonidine 1 (n = 6), 2 (13) or 3 (3) diSCS, of surface area 3.9cm2 , applied once a week, equating to a previous mean oral dose of clonidine 023, 0.32 and 036 mg/day. respectively.

Morning and afternoon mean seated BPs were 137/97 and 127/91 mm Hg, respectively, with oral clonldlne and 132/94 (p = NS/p < 0.05 vs oral clonidine) and 133/92mm Hg, respectively, with transdermal clonidine. Mean morning and afternoon plasma clonidine concentrations differed significantly (0.91 and 123 ng/ml, respectively) during oral clonidine treatment but were not significantly different (0.89 and 1.04 ng/ml, respectively) during transdermal clonidine treatment. Plasma concentrations during transdermal clonidine treatment correlated to the number of patches applied (p < 0.(01). Also, seated diastolic BP was significantly related to plasma clonidine concentrations. Drowsiness in 1 patient necessitated treatment withdrawal and 2 patients, with local skin irritation, reacted to the adhesive rather than to donidine, necessitating treatment withdrawal. 14 patients reported mild but transient local skin irritation. Other side effects to clonldme therapy commonly reported, including dry mouth, drowsiness and sexual dysfunction, were generally lessened with transdermal administration.

Thus, transdermal clonidine plus a diuretic proved effective for treating mild to moderate hypertension and was associated with a lowered incidence of side effects. Bums JF. Mroczek WJ Pharmacotherapy 6 30-34 Jan·Feb 1986

12 INPHARMA 5 Apr 1986 0156·2703/86/1005·0012/0$0100/0 © ADIS Press