Ativan is a psychoactive medication used to treat anxiety. It works by changing the chemical activity of the brain to produce a calming effect. Ativan requires a prescription and may not be purchased over-the-counter. It is a schedule IV controlled substance because of its potential for abuse. Ativan can be taken orally in the form of a pill. For faster action, Ativan can also be injected intramuscularly. Ativan is a medicine used in the treatment of anxiety disorders. It can also be used to treat insomnia, though it may not be used for longer than three weeks for this purpose. Ativan may also be used to treat other conditions, as determined by the prescriber. Ativan belongs to the benzodiazepine class of drugs and, as such, it works by enhancing the effects of GABA - the principal inhibitory neurotransmitter in the body. The active ingredient of Ativan - lorazepam - also collects in obese patients, meaning the drug takes longer to leave the body. Common side effects associated with Ativan include dizziness, drowsiness, weakness, slurred speech, and memory difficulties.