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How long does it take for Zoloft to work?

How Will You Know if Zoloft Is Working?

Zoloft isn't only for major depression. It's also used to treat obsessive-compulsive disorder, panic disorder, post-traumatic stress disorder, premenstrual dysphoric disorder (PMDD) and social anxiety disorder.

Zoloft, an oral antidepressant pill made of compressed crystalline powder, is usually prescribed to first-time users in a 50-milligram-per-day dose for depression and PMDD and 25 milligrams per day for other disorders. Dosages can be increased with time and medical supervision up to 200 milligrams per day. It's also available in liquid form [source: RX List].

Within just a few hours of taking an SSRI for the first time, the levels of serotonin in the brain and bloodstream increase. Yet, we don't feel immediate results. Zoloft takes weeks to work. Why?

The answer is us. Our bodies need time to adapt to the new normal created by taking a pill laced with sertraline that is designed to increase serotonin levels in the brain. Not only does this SSRI medication help the brain absorb serotonin into the blood stream more effectively, but it may actually change the makeup of the brain. The brain needs new receptors to help absorb the additional serotonin; it builds and installs additional receptors -- a biological process that can take up to eight weeks. So, even though Zoloft increases the levels of serotonin in our bodies nearly immediately, our brains aren't immediately equipped to absorb it [source: Crowe].

If, however, after six to eight weeks, Zoloft doesn't seem to be positively affecting your mood, anxiety -- or other condition for which it was prescribed -- it's time to alert your physician. Not every antidepressant will work the same for every person, and an estimated 50 percent of people who try an antidepressant will need to take a different brand or class before finding one that works for them. Or, it could just be that your dosage needs to be increased [source: Grohol].

Your physician will help determine your type and dosage of antidepressant by considering your symptoms, other medications you are taking, health conditions, potential side effects, and whether you are pregnant or breastfeeding. In addition, she may inquire as to whether a particular antidepressant has been taken by a close relative, and what the results were. If your brother's depression, for example, lifted after taking Zoloft, yours probably will, too [source: Mayo Clinic].