I'm wondering why can't people with acute narrow-angle glaucoma take xanax (alprazolam)?

May raise pressure. Xanax (alprazolam) can cause intraocular pressure in the eyes to go up. Even though it is generally a muscle relaxant, it may cause muscle spasms in the iris which controls the size of your pupil. If the iris contracts and blocks drainage of fluid in your eye, then pressure can build up and you may experience severe pain, blurry vision ; nausea/ vomiting. U should check w/ an ophthalmologist re: glaucoma tx.