title: Clinical safety profile of sildenafil in Singaporean men with erectile dysfunction: pre-marketing experience (ASSESS-I evaluation).
abstract: Safety and tolerability of sildenafil citrate was assessed in a population subset of 60 Singaporean men with erectile dysfunction taken from the Asian Sildenafil Efficacy and Safety Study (ASSESS-I), a double-blind, placebo-controlled, flexible-dose study. The men, from two centres, with > or = 6 months' history of erectile dysfunction, were randomized to two treatment arms for 12 weeks. One group (30 patients) received sildenafil (initial dose 50 mg taken 1 h before sexual activity for the first 2 weeks, increased to 100 mg or decreased to 25 mg, according to efficacy and/or tolerability). The remaining 30 patients received a matching placebo. Incidence and type of adverse effects were evaluated at 2, 4, 8 and 12 weeks. Nine patients (30.0%) on sildenafil (33.1% in the full ASSESS-I study) and one patient (3.3%) on placebo (22.8% in the full ASSESS-I study) experienced treatment-related adverse events, the most frequent being headache in the sildenafil group (reported by five patients [16.7%]; 11.0% in the full ASSESS-I study). Flushing, visual disturbance, dizziness, insomnia, myalgia and back pain each occurred in one patient in the sildenafil group (3.3%); in the placebo group, one patient (3.3%) had headache. Importantly, the incidence of cardiovascular and respiratory system adverse events were relatively less than in the full ASSESS-I population (cardiovascular 3.3% in the present study versus 10.2% in the full ASSESS-I population; respiratory 3.3% versus 5.5%). All adverse events were transient and mild, and did not lead to treatment withdrawal. There was no effect on sitting blood pressure, heart rate or standard laboratory parameters; more importantly, there was no incidence of myocardial infarction, stroke or priapism. These results should reassure Singaporean patients and their physicians of the safety of sildenafil for erectile dysfunction.
authors.affiliation: Department of Urology, Changi General Hospital, Singapore. tphphcl@pacific.net.sg
authors.forename: P H C
authors.initials: PH
authors.lastname: Lim
authors.forename: F C
authors.initials: FC
authors.lastname: Ng
authors.forename: C W S
authors.initials: CW
authors.lastname: Cheng
authors.forename: M Y C
authors.initials: MY
authors.lastname: Wong
authors.forename: C T Y
authors.initials: CT
authors.lastname: Chee
authors.forename: P
authors.initials: P
authors.lastname: Moorthy
authors.forename: S S
authors.initials: SS
authors.lastname: Vasan
mesh_terms: D000328:Adult; D004311:Double-Blind Method; D007172:Erectile Dysfunction / Q000188:drug therapy*; D006801:Humans; D008296:Malaysia; D008297:Male; D040541:Marketing; D008875:Middle Aged; D010679:Philippines; D010879:Piperazines / Q000009:adverse effects* / Q000627:therapeutic use; D010919:Placebos; D011687:Purines; D000068677:Sildenafil Citrate; D012846:Singapore; D013450:Sulfones; D014665:Vasodilator Agents / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D010879:Piperazines; D010919:Placebos; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate