Is 1 mg of Xanax a lot? Yes, 1 mg of xanax is considered a very high dose. This is especially true for people who are not used to xanax or have a low tolerance for xanax. xanax is a powerful drug used to treat anxiety disorder and panic attacks. Even at a lower dose, xanax can cause serious side effects. At 1 mg, xanax has a sedative and calming effect. This helps to reduce anxiety symptoms and promotes relaxation.