From the FDA Drug Label
The blood level decline of the parent drug was biphasic with the short half-life ranging from 0.4 to 0.6 hours and the terminal half-life from 3.5 to 18.4 hours (mean 8. 8 hours), depending on the study population and method of determination.
The half-life of Temazepam is biphasic, with a short half-life of 0.4 to 0.6 hours and a terminal half-life of 3.5 to 18.4 hours (mean 8.8 hours). There is significant variability between individuals due to differences in study population and method of determination. 1
From the Research
Half-Life of Temazepam
- The half-life of temazepam is reported to be around 10 to 15 hours 2, 14.7 hours 3, and 5 to 11 hours 4.
- However, one study found that the temazepam elimination half-life ranged from 8 to 38 hours, indicating significant variability between individuals 5.
Variability in Half-Life
- The variability in half-life may be due to factors such as age and gender, with women having a longer half-life than men (16.8 vs 12.3 hours) 5.
- Additionally, the half-life may be influenced by individual differences in protein binding, with the free fraction of temazepam increasing with age 5.
- The study also found that clearance of unbound temazepam was higher in men than in women, and tended to decline with age in both sexes 5.
Comparison with Other Benzodiazepines
- Temazepam has a relatively short half-life compared to other benzodiazepines such as flurazepam, which has a half-life of around 72 hours 6.
- However, the clinical relevance of the plasma elimination half-life of benzodiazepines may be overestimated, as one study found no difference in efficiency reduction between temazepam and flurazepam despite their differing half-lives 6.