Hi, Xanax contains alprazolam that belongs to the group of medications known as benzodiazepines is used in the treatment of anxiety, insomnia etc. But like other medications this medication has some side effects of its. Stop taking Xanax abruptly can cause some unpleasant symptoms which is known as withdrawal syndrome. Withdrawal syndrome of this medication are insomnia, troubling dreams, restlessness, awakenings while sleeping, irritation or agitation, loss of attention, forgetfulness, tension, muscle aches, sweating, headache, loss of interest, rebound anxiety, suicidal thoughts and many more. If someone wants to stop taking this medication, then he or she should inform his or her doctor first and try to stop taking this medication gradually by following a tapering schedule under supervision of the prescribing doctor. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zubayer Alam General And Family Physician