From the Research
Onset of Action of Zopiclone
- The onset of action of zopiclone is not explicitly stated in the provided studies, but its pharmacokinetic properties can give some insight into how quickly it starts to take effect.
- Zopiclone is rapidly absorbed after oral administration, with a bioavailability of approximately 80% 1.
- It is also rapidly and widely distributed to body tissues, including the brain 1.
- The terminal elimination half-life of zopiclone ranges from 3.5 to 6.5 hours 1, which suggests that it starts to take effect relatively quickly.
- Studies have shown that zopiclone improves sleep in chronic insomniacs, with minimal impairment of psychomotor skills and mental acuity in the morning after a bedtime dose 2, 3.
- The exact onset of action of zopiclone is not specified, but its rapid absorption and distribution suggest that it starts to take effect within a short period of time after administration.
Pharmacokinetic Properties
- Zopiclone has a short half-life of about 5 hours and no long-acting metabolites 2.
- It is partly metabolized in the liver to form an inactive N-demethylated derivative and an active N-oxide metabolite 1.
- Approximately 50% of the administered dose is decarboxylated and excreted via the lungs 1.
- Less than 7% of the administered dose is renally excreted as unchanged zopiclone 1.
Clinical Efficacy
- Zopiclone has been shown to be effective in the treatment of insomnia, with improvements in sleep quality and duration 2, 3.
- It has a relatively low propensity to cause residual clinical effects, such as difficulty in waking or reduced morning concentration 3.
- Zopiclone is well tolerated in both the elderly and younger patients with insomnia, with a bitter aftertaste being the most common adverse event 3.