The disposition of alprazolam in 16 young healthy volunteers (eight females and eight males) was investigated. All volunteers were given a 1 mg dose of alprazolam. Dose/kg was 13.3 micrograms/kg (SD +/- 0.89 micrograms/kg) on average for male volunteers and 17.5 micrograms/kg (SD +/- 1.84 micrograms/kg) for the female volunteers. Pharmacokinetic parameters were calculated separately for both sexes in order to detect possible gender-dependent differences. The elimination rate constant (beta) for alprazolam proved to be significantly higher in the female population 0.067 hr-1 vs. 0.053 hr-1 (p = 0.03). The closely related parameters, elimination half-life (t1/2) and clearance (Cl) were also significantly different. The total area under the serum concentration curve (AUCtot), maximum serum concentration (cmax) and volume of distribution (Vd) were not significantly different. AUCtot corrected for differences in dose/kg was on the other hand significantly higher in males (p = 0.003) while cmax corrected in the same manner was not.
The present study analysed changes in sex-specific suicide rates in Canada from 1971 to 1985. A significant increase in the male-to-female ratio of suicide rates was observed. Our analysis of sex-specific age-adjusted rates revealed that this increasing ratio was a function of both increasing male rates and decreasing female rates, but that the latter was more marked. This divergence of male and female rates within the last decade and a half parallels similar changes noted both in the US and in the majority of European countries, but contrasts with a pattern of converging rates throughout North America and much of Europe prior to 1970.