-- Question: Are all antidepressants the same, and how long will it take for antidepressant treatment to help with my anxiety disorder?
Answer: All antidepressants are not the same. Whereas earlier studies showed that all the SSRIs may be equally efficacious in depression, more recent studies have shown that there are differences not only in the effects of the antidepressants, but in the side effects. Drugs that may have prominent and potent effects, such as pregabalin, or MAO inhibitors, may actually have more side effects associated with them than drugs that have intermediate effects such as SSRIs. As a result of this, a clinician may chose to use an SSRI in order to limit side effects, but to use drugs that have at least an intermediate potency.
With regard to how long these drugs take to act, these drugs generally take approximately four to six weeks before therapeutic effect can be seen. With a lot of people, waiting this long becomes intolerable. Due to this, drugs such as benzodiazepines may be used in the first four to six weeks in order to decrease the anxiety immediately, while the other drugs, such as SSRIs, are taking their time to act. For obsessive compulsive disorder, the time to action may be a little longer. And may be more in the range of eight to 12 weeks rather than four to six weeks.