do not take intermezzo if you have had an allergic reaction to drugs containing zolpidem, such as ambien. allergic reactions such as shortness of breath or swelling of your tongue or throat may occur and may be fatal. intermezzo should not be taken if you have taken another sleep medicine at bedtime or in the middle of the night or drank alcohol that day. do not drive or operate machinery until at least 4 hours after taking intermezzo and you're fully awake. driving, eating, or engaging in other activities while not fully awake without remembering the event the next day have been reported. abnormal behaviors may include aggressiveness, agitation, hallucinations, or confusion. alcohol or taking other medicines that make you sleepy may increase these risks. in depressed patients, worsening of depression, including risk of suicide, may occur. intermezzo, like most sleep medicines, has some risk of dependency. common side effects are headache, nausea, and fatigue. so if you suffer from middle-of-the-night insomnia, ask your doctor about intermezzo