When it comes to psychiatrists and doctors prescribing antidepressant medications like Paxil for patients, a lot of that process is trial and error or guesswork. Patients can suffer the side effects of various pills before finally finding one that works in treating their major depressive symptoms. In some cases, doctors even use more than one antidepressant if they think it will work. However, all of that guesswork soon may be over.

It turns out that a company called AssureRx Health is now offering something called GeneSightRx, which is a term used for what the company calls “pharmacogenomic” laboratory testing. The test is meant to help patients identify which antidepressants will work well for them by testing their genetic makeup. In some cases, the test will also reveal why some antidepressants haven’t worked at the same time that it points out which antidepressant might work.

This new genetic test may be the best thing to happen to depressed patients and doctors alike, as it may give patients the chance to take the right medication the first time rather than risk the chance of suffering from serious adverse side effects from taking some medications. For example, patients who take SSRI medications like Paxil risk suffering from violent and suicidal thoughts or actions. Women taking Paxil risk having their babies born with birth defects (PPHN, cleft palate, spina bifida and other neural tube defects) when they take the drugs during the first trimester of pregnancy.

This new test works by finding out which genetic variants or enzymes get activated in each individual with each antidepressant. Since different antidepressants work on enzymes in different ways, this test could be used to predict accurately how specific drugs will work in an individual patient before they take it. The test may also determine which drugs will cause the least side effects.