How long on average does it take for lorazepam(ativan) to have an affect?

Answer 1

10-30 minutes onset if given orally - wikipedia says it takes longer to come on, but I've seen it come on reasonable quickly in psychiatric patients who are fairly disturbed.

Answer 2

Lorazepam – Ativan, Temesta, Tavor, is a drug which is a benzodiazepine derivative. Pharmacologically, it is classified as a sedative-hypnotic, anxiolytic and anticonvulsant. It is used to relieve anxiety, it is also used to treat irritable bowel syndrome, epilepsy, insomnia, and nausea and vomiting from cancer treatment and to control agitation caused by alcohol withdrawal. Talk to your doctor about the possible risks of using this drug for your condition.
Lorazepam comes as a tablet and concentrate (liquid) to take by mouth. It usually is taken two or three times a day and may be taken with or without food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take lorazepam exactly as directed.Lorazepam is rapidly and nearly completely absorbed after any mode of application (oral, sublingual) The onset of action is several minutes after i.v. injections, 30 to 45 minutes after oral/sublingual administration, and up to 1 hour after i.m. injections.The duration of action depends on the dose, and is normally 6 to 12 hours. The half-life of lorazepam in patients with normal liver function is 11 to 18 hours. Therefore, 2 to 4 daily doses are often needed.
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