788 healthy adults who suffered from insomnia—sleeping less than 6.5 hours per night and/or taking more than 30 minutes to fall asleep—for at least a month were given Lunesta or a placebo nightly for 6 months. Here’s what happened.

What Difference Did Lunesta Make?Starting Risk
(Placebo group)
Modified Risk
(Lunesta group, 3 mg/night)
Did Lunesta help?
Lunesta users fell asleep faster
(15 minutes faster due to drug)
45 minutes to fall asleep30 minutes to fall asleep
Lunesta users slept longer
(37 minutes longer due to drug)
5 hours, 45 minutes of sleep6 hours, 22 minutes of sleep
Did Lunesta have side effects?
Life-threatening side effects0% in both groups
No difference between Lunesta and placebo(none observed in this study)
Symptom side effects
Unpleasant taste in the mouth
(additional 20% due to drug)
6 in 100
26 in 100
Infections (mostly colds)
(additional 9% due to drug)
7 in 100
16 in 100
(additional 7% due to drug)
3 in 100
10 in 100
Next-day drowsiness
(additional 6% due to drug)
3 in 100
9 in 100
Dry mouth
   (additional 5% due to drug)
2 in 100
7 in 100
(additional 5% due to drug)
6 in 100
11 in 100

From: Chapter 7, Do the Benefits Outweigh the Downsides?

Cover of Know Your Chances
Know Your Chances: Understanding Health Statistics.
Woloshin S, Schwartz LM, Welch HG.
Berkeley (CA): University of California Press; 2008.
Copyright © 2008, The Regents of the University of California.

Know Your Chances: Understanding Health Statistics is hereby licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported license, which permits copying, distribution, and transmission of the work, provided the original work is properly cited, not used for commercial purposes, nor is altered or transformed.

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