The best treatment for anxiety is a combination of relaxation techniques and cognitive therapy. Relaxation techniques help you let go of things that you can't control. Cognitive therapy helps change your thinking, so that you won't make yourself anxious.
The most common anti-anxiety medications are benzodiazepines (benzos) like Valium and its relatives. Recently a new class of drugs has been developed that are strictly speaking non-benzodiazepines, but they have the same side effects and risks.
These are some of the common tranquilizers and sleeping pills, and their generic names.
1) All tranquilizers are potentially addictive. If you take them for longer than a month, you will probably develop some dependence on them, and you will probably experience some withdrawal when you stop using them.
2) Long-term use of tranquilizers increases your anxiety. If you use tranquilizers for longer than a month, they can increase your anxiety and disturb your sleep. The irony is that tranquilizers are prescribed to help anxiety and sleep. This is what makes them the perfect addictive drugs. The longer you use them, the more you need them.
3) Tranquilizers are brain depressants. If you take them for longer than a month, they can increase your chances of becoming depressed.
4) Tranquilizers block the effectiveness of antidepressants. If you take them for more than a month, any antidepressants you're taking will be less effective, and you may feel more depressed or anxious.
Check with your doctor to make sure there are no other medical causes for your anxiety. For example, you should have your thyroid checked. If there are no other medical causes for your anxiety, and you cannot control your anxiety with relaxation techniques and cognitive therapy, then you might want to discuss the possibility of an antidepressant with your doctor.
Why are tranquilizers still prescribed? They can be helpful for short-term anxiety or sleeplessness. Some people need them to deal with unusually stressful situations. But if you take them for longer than a month, your body will adapt to them, your anxiety level may rise, and you may need more of them over time. (Reference: Anxiety and Depression Guide)
Consider an antidepressant instead of a tranquilizer. If your anxiety is so severe that you need medication, antidepressants are usually a better choice than tranquilizers. Why? Because anxiety is one of the common symptoms of depression.
Antipsychotic medication is sometimes used to relieve the symptoms of anxiety, in serious cases. This is because antipsychotic medication is sedating besides being antipsychotic. However, antipsychotic medication can have permanent neurological consequences if taken for more than a few years, such as tremors, akathisia, parkinsonism, and tardive dyskinesia. The most common antipsychotic medication that is used to treat anxiety in the short-term is Seroquel (quetiapine).
1) D Poyares, C Guilleminault, MM Ohayon, S Tufik, "Chronic benzodiazepine usage and withdrawal in insomnia patients," Journal Psychiatric Research (2004) May-Jun;38(3):327-34.