Ambien CR is an extended-release version of the sedative-hypnotic drug, zolpidem tartrate. Prescribed for short-term sleep disorders such as insomnia, zolpidem corrects the underlying chemical imbalance and allows the brain to relax and rest. According to the Ambien CR website, the drug is formulated in two layers that dissolve at different rates, offering significant advantages to those seeking a good night's sleep.
Rapid Effect
The top layer of Ambien CR dissolves rapidly, is absorbed into the bloodstream and travels to the brain where it changes the chemical balance that affects sleep. The pill should be taken right before bedtime with a full glass of water, since it works within 15 to 30 minutes, according to the manufacturer, Sanofi-aventis.
Sustained Sleep
The second layer of Ambien CR dissolves more slowly and continues to affect the brain for 7 to 8 hours to maintain sleep. Ambien CR is not to be taken if the user will be traveling on an airplane or be in a situation where he can't stay in bed for 7 hours or more, notes PubMed Health.
Less Wakefulness
People with sleep disorders may be able to fall asleep, but they experience disturbing periods of wakefulness throughout the night that interfere with a normal sleep pattern. According to the Ambien CR website, in clinical trials conducted by Sanofi-aventis, individuals who took Ambien CR awakened less often than those who took a placebo.
No Addiction
Unlike other medications used to promote sleep, Ambien CR is not a narcotic or a barbiturate with established addiction potential. People who take the drug as prescribed don't develop a tolerance to Ambien CR or need higher doses to reach the same effect, according to the Ambien CR website. However, some people who take zolpidem do develop drug dependency and have difficulty weaning themselves off the drug.
Long-Term Effect
The U.S. Food and Drug Administration has approved the extended release form of zolpidem for long-term use in people with sleep disorders. In a 24-week study conducted by the manufacturer, patients taking Ambien CR said they slept longer and enjoyed a better quality of sleep throughout the study period. They continued to appreciate the benefits of the drug without the rebound wakefulness seen with some other sleeping pills.
