Double-blind comparison of the hypotensive, sedative and salivary flow effects of lofexidine and clonidine in normal subjects.
A double-blind crossover comparison was made of the hypotensive, sedative and salivary flow effects of a single 300 microgram dose of either 2-[1-[2,6-dichlorphenoxy)-ethyl]-2-imidazoline hydrochloride (lofexidine. Lofetensin and Loxacor) or clonidine in six normal young men. Both drugs caused a significant fall in recumbent blood pressure. Systolic and diastolic pressure was reduced from 1 to 12 h after the dose with clonidine and from 2 to 8 h after it with lofexidine with peak effect being observed between 2 and 4 h with both drugs. The reduction of blood pressure 2 and 4 h after the dose was greater with clonidine than lofexidine. Reduction in salivary flow was significant from 1 to 12 h after the dose with clonidine but only from 1 to 8 h with lofexidine. The minimum value of salivary flow was 0.096 g/min after clonidine and 0.205 g/min after lofexidine. After clonidine the sedative effect was significant from 1 to 8 h after the dose and with lofexidine from 2 to 8 h after it. Peak sedation was similar with the two drugs. A 300 microgram dose of lofexidine has slightly less hypotensive effect than a 300 microgram dose of clonidine. The duration of the hypotensive effect was 2-3 h shorter with lofexidine than with clonidine. The sedative effect of both drugs was similar but lofexidine had less effect upon salivary flow.
D000328:Adult; D000959:Antihypertensive Agents; D001794:Blood Pressure / Q000187:drug effects; D003000:Clonidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000494:pharmacology*; D004311:Double-Blind Method; D004562:Electrocardiography; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives; D008297:Male; D012472:Salivation / Q000187:drug effects*
D000959:Antihypertensive Agents; D006993:Hypnotics and Sedatives; D003000:Clonidine; C025655:lofexidine