Anti-Anxiety Medication Is Fueling US Drug Crisis Anxiety is the most common mental illness in the United States. Over 40 million Americans suffer from the condition. There has been a 67% rise in anti-anxiety medication prescriptions. The market for benzodiazepines such as Xanax, Ativan, Librium and Valium is expected to reach $3.8 billion in the U.S. by 2020. But there's been a huge increase in overdoses on anti-anxiety medication. The withdrawal process for benzodiazepines is even more dangerous than opioids. Dr. Anna Lembke, Stanford Addiction Medicine Dual Diagnosis Clinic, via NBC