Zolpidem in insomnia: a 3-year post-marketing surveillance study in Switzerland.

A multicentre post-marketing surveillance study was conducted in Switzerland in routine practice and involved 1972 insomniac patients treated with zolpidem, an imidazopyridine hypnotic agent. The patients were representative of the general insomniac population (65% women; mean age 55 years; 29% over 65). Of the patients, 87% were treated with a zolpidem dosage of 10 mg/day and the median treatment duration was 30 days. All adverse events were collected through spontaneous reporting. A total of 175 patients (8.9%) reported 343 adverse events, and 102 (5.2%) of them discontinued treatment. CNS (central nervous system)-related adverse events accounted for 66% of the total, the most common events being residual daytime sedation and insufficient efficacy in 3.7% and 1.6%, respectively; confusion, disorientation, nervousness, nightmares, amnesia, impaired concentration and anxiety were observed in a lower proportion. Gastro-intestinal symptoms, headache and skin reactions were the most frequent non-CNS related effects. No serious adverse event was reported and no new risk factors or at-risk populations were identified. The safety profile of zolpidem is thus consistent with its known pharmacological properties, the results of previous clinical trials, and the cumulative international experience gained with this short-acting hypnotic drug.

Drugs effect on platelet survival time: comparison of two pyrimido-pyrimidine derivatives in patients with aortic or mitral replacement.

A prospective randomized trial of the effects of 2 antiplatelet aggregating drugs, dipyridamole (375 mg/d), a related substance RA 233 (1500 mg/d) and placebo, concomitantly with oral anticoagulants, was carried out in patients with prior valvular replacement. The study was aimed to determine effect on platelet survival time (PST) of these 2 agents. The trial sample consisted of 40 males and 15 females aged 40-70 years (average 53 years). 32 received Björk-Shiley valve in aortic position, 23 underwent mitral valve replacement: 3 with Cooley-Cutter, 11 with Lillehei-Kaster 500 and 9 with Starr-Edwards 6120 prostheses; 28 patients had aortic stenosis, 21 aortic insufficiency. All the PST measured after 3 months of treatment were within normal ranges and not different between placebo, dipyridamole or RA 233 treated subjects: averages in days were, respectively, 7.49, 7.11 and 6.88. The present study did not support the claim that modern valve prosthesis could lead to a shortened PST.