If in our discussions you and I decide that medication is right for you, but we have trouble finding one that works well for you, or you have difficulty tolerating one or more medications, I may suggest genetic testing.
Genetic testing looks at many of the genes involved in processing certain medications. Since people differ in their genetic makeups, they respond differently to different medications. Genetic testing can help determine which medications are likely to be helpful to you, based on your individual DNA.
There are several companies that provide this testing, I use one called, Genesight. The test itself is performed by me, in my office, and involves a simple and painless swab of the inside of your cheek. I then send the sample to Genesight, and in a few days, they send back a report, with information about which psychiatric medications you're more likely to tolerate well, and which you're more likely to respond to well.
The test is not foolproof. In general, I have found that it's better at predicting which medications you can tolerate well, than which medications will be most helpful for what we're trying to treat. But it can still be useful, and may be worth trying if we're struggling to find the right medication for you.