Less than we thought. Similar to recent recommendations to lower the bedtime dose for Ambien (zolpidem) from 10 mg to 5 mg, the FDA has announced that the manufacturer of Lunesta (eszopiclone is the generic) will be required to change the current recommended starting dose. The recommended starting dose of Lunesta has been decreased from 2 mg to 1 mg for men and women. The 2 mg and 3 mg doses could lead to next-day impairment of activities requiring alertness such as driving.
Remember that Lunesta (eszopiclone) is longer acting than zolpidem. The half-life of Lunesta is 6 hours compared to 2.5 hours for immediate release zolpidem (Ambien). The problem here is that research shows eszopiclone levels in some patients after waking may be high enough to impair activities requiring alertness, even if the patient feels fully awake.
How do we know this? A study of 91 healthy adults ages 25 to 40 found that Lunesta 3 mg was associated with severe next-morning psychomotor and memory impairment 7.5 hours after taking the drug in both men and women. What is really crazy is that recommended doses were shown to cause impairment to driving skills, memory, and coordination for up to 11 hours after the drug is taken and the patients were unaware they were impaired. So patients didn’t report feeling impaired, but they were.
Patients that are currently taking the 2 mg or 3 mg doses of eszopiclone should talk to their doctor about a change.