A new hypnotic agent zaleplon (Sonata) has been launched. The drug was developed by Wyeth, which holds the product licence, and is being marketed in partnership with Lundbeck. Wyeth will distribute the drug while Lundbeck will promote and market it and provide drug information services.
Zaleplon is a non-benzodiazepine hypnotic which is rapidly absorbed and eliminated, with a half life of around one hour. As a result, the drug has been shown to have minimal residual effects the next day.
Zaleplon is licensed for use in patients with insomnia who have difficulty falling asleep (see p384). Lundbeck says that, because of the rapid onset of action, flexible dosing can be used whereby a patient could try to sleep without treatment and then take the drug only if they then have difficulty getting to sleep.
The company adds that zaleplon could also be taken during the night if a patient wakes up and has trouble falling back to sleep, as long as they will be staying in bed for another four hours. Patients should not, however, take a second dose within a single night.
Zaleplon is formulated with a marker substance which allows detection if, as reported with Rohypnol, the drug were to be used to "spike" drinks. If the capsule contents are dissolved in a liquid, the liquid will change colour and become cloudy.
Zaleplon acts at the GABA-benzodiazepine receptor complex, although it is unrelated to existing hypnotics.