Uses This medication is used to treat anxiety. Lorazepam belongs to a class of drugs known as benzodiazepines which act on the brain and nerves (central nervous system) to produce a calming effect. This drug works by enhancing the effects of a certain natural chemical in the body (GABA). How to use Ativan Read the Medication Guide provided by your pharmacist before you start taking lorazepam and each time you get a refill. If you have any questions, ask your doctor or pharmacist. Take this medication by mouth with or without food as directed by your doctor. The dosage is based on your medical condition, age, and response to treatment. If directed by your doctor, use this medication regularly in order to get the most benefit from it. To help you remember, use it at the same time(s) each day. If you suddenly stop using this medication, you may have withdrawal symptoms (such as seizures, trouble sleeping, mental/mood changes, nausea, vomiting, diarrhea, loss of appetite, stomach pain, hallucinations, numbness/tingling of arms and legs, muscle pain, fast heartbeat, short-term memory loss, very high fever, and increased reactions to noise/touch/light). To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used lorazepam regularly for a long time (more than 1-4 weeks) or in high doses or if you have a history of alcoholism, drug abuse, or personality disorder. Tell your doctor or pharmacist right away if you have withdrawal.