Ativan has a relatively short half-life of between 10 and 12 hours, and withdrawal symptoms may start within 24 hours of the last dose. Early withdrawal usually is indicated by a kind of bounce back by the brain, causing a rush of anxiety as well as increased heart rate and blood pressure and difficulties sleeping. As withdrawal symptoms from Ativan can be dangerous, high dose and long-term users are advised to undergo medically supervised detox. Detoxing from any benzodiazepine is difficult and can be dangerous. Ativan Withdrawal and Detox. Withdrawal from Ativan causes symptoms like anxiety, nausea and irritability. Medically-assisted detox can help to reduce these symptoms and make the process safer. Benzodiazepine withdrawal can be severe and can provoke life-threatening withdrawal symptoms, such as seizures, particularly with abrupt or overly rapid dosage reduction from high doses or long time users. From a clinical standpoint, these long-term symptoms are not considered to be symptoms of withdrawal per se, but rather the after effects of having abused Ativan or other benzodiazepines on a long-term basis. Questions and Answers (FAQ) How Long Does Ativan Withdrawal Last? Typically, symptoms develop within 24 hours, peak around the second day, and improve by the fourth or fifth day. Ativan Withdrawal Duration: How long does it last? It is important to understand that there is no set withdrawal “timeline” or set period of time that the withdrawal is going to take. For some people, symptoms may last for several weeks and subside. For one, people with anxiety issues are prone to addiction BECAUSE of the desire to self medicate to squash the symptoms. Depending on how long you've been taking the Vicodin, you may have w/d symptoms when you stop taking it, which I would highly recommend you do. Benzodiazepine withdrawal can result in life-threatening withdrawal symptoms. Medical supervision and a tapered approach are needed. Medical supervision and a tapered approach are needed. In a personal essay for Tonic , Harriet Brown wrote about her experiences with quitting Ativan. Ativan (lorazepam) is a member of the benzodiazepine class of drugs. Benzodiazepines are used primarily in the treatment of anxiety, seizure disorders, and as muscle relaxants.