What Are Benzodiazepines and Z-drugs?

Benzodiazepines, also known as BZs or benzos, are commonly prescribed for anxiety, insomnia, muscle tension and a variety of other problems. Many different drugs are classified as benzodiazepines, a group that includes well-recognized brand names such as Xanax®, Valium®, Ativan® and Klonopin®. All share a common chemical structure and all achieve their desired effect by modifying a specific receptor site on neurons. Benzos have been prescribed for many years (click here for the Wikipedia version of the history of benzos, and here for a longer version from BenzoInfo.com), and over 120 million prescriptions are written each year in the U.S. According to the National Institute of Health, between 1996 and 2013, the number of adults who filled a benzodiazepine prescription increased by 67%. Physiological dependence can develop with any benzodiazepine, and the associated withdrawal syndrome can be very difficult. All benzos are therefore very dangerous to some patients.

Another class of drugs, known as “Z-drugs”, have effects that are somewhat similar to benzos. They are primarily prescribed as sleeping aids. They share a common method of action with benzos, but differ in other ways. They are perceived to be safer than benzos, and in certain respects they may be. However, this is a matter of much debate, and use of Z-drugs can result in adverse outcomes of the same type and severity as benzodiazepines.

There are at least 132 undesirable (“side”) effects that are possibly or definitely due to benzodiazepines and Z-drugs. These range from rare to very common, and from mild to severe. Due to the frequency of occurrence, there is particular concern about cognitive (e.g., memory, amnesia, poor judgment and decision-making, dementia) and psychomotor (e.g., balance, coordination, driving, injuries, fractures) problems, and often marked negative effects on functional capacity. Benzodiazepines have been associated with a range of negative outcomes, including decreased quality of life, increased overall mortality, suicide, and death related to opioid overdose.

According to the American Psychiatric Association, physiological dependence and a resulting withdrawal syndrome may be seen in to up 80% of patients who use benzodiazepines long-term.^[1] Symptoms (at least 78 reported) of the withdrawal syndrome range from trivial to long-lasting and catastrophic. Treatment for withdrawal syndrome is helpful, both with medication and non-medication approaches. Benzodiazepine and Z-drug physiological dependence is discussed here; for an in-depth discussion of the associated and withdrawal syndrome, click here.

“Dependence”, “addiction”, “abuse” and “physiological dependence” are terms that are often used interchangeably but actually have quite different meanings. Please see “The Language of Harmful Use” for an overview of this difference, and the Terminology page for a detailed description of each of these terms. By using the appropriate terminology, we can both demonstrate understanding and help educate others.