Two recent studies now show that once someone with depression has tried and failed two medications, TMS is more likely to be effective than a third mediation trial. 

This very important data, since up until now, we had very little solid evidence about when TMS becomes more effective. There were hints from years ago that it happened around three or four medication failures, but nothing conclusive. Also, we have learned a lot over time about how best to do TMS, and so many of us suspected it now stands up better against meds.

Many people suffering from major depression will improve with the first antidepressant they try, but a lot will not. Each time a person has to try another medication, the chances increase that they are not someone who responds to medications, and so the chance that the next medication will work decreases. By the time one gets to their fourth medication, the probability of resolving the depression is only about 7%.

TMS is a completely different approach to treating depression as it does not work through brain chemistry at all; it uses a magnetic field to strengthen the connections between brain cells in a region of the brain that regulates emotion. As a result, the fact that a person hasn’t responded to several medication trials does not cast a shadow on their chances of responding to TMS. 

Head-to-head studies of medical treatments are surprisingly few and far between, and I never expected to see one comparing antidepressant medications to TMS. But just in the past several months, not one, but two, came out and now we know that doctors and patients should be thinking about trying TMS over medications sooner than we had suspected; even as soon as two failed trials.