What Is the Difference between Clonazepam and Xanax®?

Clonazepam and Xanax® (alprazolam) are two commonly prescribed benzodiazepine medications. Each works effectively for anxiety, but clonazepam is also used as a muscle relaxant and anti-seizure drug. The medications differ in how quickly they work, how long they stay in the body, and how appropriate they are for certain conditions. Benzodiazepines share similar side effects, but clonazepam side effects may be more noticeable.

Perhaps the biggest difference between clonazepam and Xanax® is that clonazepam is used in a greater number of applications. Physicians sometimes employ the drug to treat the sudden onset of a seizure, or they may use it long-term in the treatment of seizure disorders. Clonazepam is not a first-line treatment for many seizure conditions; generally, doctors use another benzodiazepine called lorazepam for emergency treatment of seizures.

Clonazepam is also used as a muscle relaxant. Again, a similar benzodiazepine, diazepam, may be preferred to clonazepam, in this respect. Clonazepam at least can be effective, and may work slightly longer than diazepam. It might be useful to prescribe for patients who have already developed diazepam tolerance.

Benzodiazepines are often classed as short, intermediate, and long-acting, referring to drug half-life, or the time it takes a medication to be reduced by half in the body. A difference between clonazepam and Xanax® is that they aren't in the same class. Clonazepam is an intermediate-acting drug, and Xanax® is short-acting. The expected half-life of Xanax&reg is six to 12 hours, and in clonazepam the half-life is 18 to 50 hours.

Though the half-lives are different, the time it takes these two drugs to work fully is similar. Xanax® is usually most effective within one to two hours of ingestion, and clonazepam can go to work as quickly as Xanax® or it may take up to four hours to be fully effective. In this way, the two drugs are nearly comparable and may both provide quick relief to anxiety.

Physicians may compare clonazepam and Xanax® by their usefulness to treat certain conditions. Since Xanax® has a shorter half-life, it is associated with quicker development of drug tolerance. Long-term use is complicated because it may require continually increasing doses to provide the same effects.

Due to this, clonazepam may be used more frequently to treat anxiety that is long-standing. Xanax® is more often considered for short-time use. Essentially, clonazepam's half-life suits it better for daily use, though it ultimately creates dependence, too.

Differences regarding side effects are often related to the half-life of clonazepam and Xanax®. Quicker clearance of Xanax® usually means that side effects like drowsiness, poor concentration, and motor skill impairment may be noticed less and are unlikely to persist for long. Given the much longer half-life of clonazepam, some patients could note side effects for several days. Some patients prefer alprazolam's quicker clearance to avoid side effects, while others may choose the longer coverage of anxiety symptoms that clonazepam can provide.