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Ask the Experts


I have a 30 minute college presentation coming up which will take place during a 3 hour class.

I suffer with social anxiety disorder so my psychiatrist prescribed me 0.5mg of xanax. I was advised to take half a pill, and only the other half if my anxiety hasn't lessened.

What I'd like to know is how long does 0.25mg of xanax take to kick in, and how long will it last? Is it best to take on an empty stomach?

I'm female, 5 foot 3 inches and 55kg.

Answered by: Franklin Schneier

Most people find that a single dose of Xanax kicks in within 15-30 minutes and anti-anxiety benefits last a few hours. Food generally does not affect its actions. 0.25 mg is a very reasonable dose, but there is a great deal of variation among individuals in the effect of a particular dose of xanax, and it is not predicable on the basis of height or weight. So you might want to try a "test dose" in advance to see how it affects you (and to give you one less thing to worry about). Drowsiness is the most common side effect.