A placebo-controlled, crossover trial of granisetron in SRI-induced sexual dysfunction.
BACKGROUND
Sexual side effects are commonly associated with serotonin reuptake inhibitor (SRI) therapy. The mechanism underlying SRI-induced sexual dysfunction has been hypothesized to be mediated by direct serotonergic effects. Evidence from open-label reports suggests that cyproheptadine, nefazodone, mirtazapine, and mianserin, which block one or more serotonin receptors, may reverse sexual side effects. The current study was a prospective, randomized, crossover trial comparing granisetron, a serotonin-3 antagonist, with placebo in outpatients who developed sexual dysfunction during SRI treatment.


METHODS
Thirty-one outpatients who were currently experiencing sexual dysfunction associated with SRIs were randomly assigned to double-blind treatment with granisetron (1-1.5 mg) or placebo for use 1 to 2 hours prior to sexual activity. Patients rated sexual symptoms after each trial using the Sexual Side Effect Scale (SSES). After 4 trials of the medication, patients crossed over to the other treatment for 4 more trials.


RESULTS
Twenty patients received at least 1 dose of placebo and granisetron. Analysis by repeated-measures analysis of variance showed no significant effects of granisetron relative to placebo. Significant improvement between baseline and treatment-phase SSES scores was observed for both granisetron (p = .0004) and placebo (p = .0081). The study medication was generally well tolerated.


CONCLUSIONS
The results of this study do not support the efficacy of granisetron (1-2 mg) in the treatment of SRI-associated sexual side effects. A significant placebo response may be associated with the treatment of SRI-induced sexual dysfunction.
Nelson
E B
EB
Department of Psychiatry, University of Cincinnati College of Medicine, Ohio 45267-0559, USA.
Shah
V N
VN
Welge
J A
JA
Keck
P E
PE
D000553:Ambulatory Care; D000704:Analysis of Variance; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D017829:Granisetron / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D012702:Serotonin Antagonists / Q000627:therapeutic use*; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D020018:Sexual Dysfunctions, Psychological / Q000139:chemically induced* / Q000188:drug therapy* / Q000523:psychology; D016896:Treatment Outcome
D017829:Granisetron; D010919:Placebos; D012702:Serotonin Antagonists; D017367:Selective Serotonin Reuptake Inhibitors