Light Therapy, Antidepressant Meds—Either/Or? Both?

Originally published in:
Michael Terman, PhD

Light Therapy, Antidepressant Meds—Either/Or? Both?

What will it take to do away with depression’s symptoms?


With such a complicated picture, it should be clear that any particular treatment wouldn’t work for everyone. And, truth be told, it is very unlikely that a clinician will be able to predict which will work for you. So that means trial and error. You go cycling through meds and varying doses of meds until — with luck — you reach an acceptable outcome. Even then it is rare that a drug will eliminate all of your symptoms. “Residual symptoms” are expected, unless the depression fully remits on its own. Even with significant improvement, the more the residual symptoms, the more you are likely to experience a relapse in the near or distant future. Not a pleasant thought.

“The relative lack of progress in the treatment of psychiatric disorders is a crisis and the solution to this crisis, the emergence of new paradigms . . . cannot be simply more research following established formulae.” — John Krystal, M.D., Yale Psychiatry. Other experts have lamented, “We still don’t have any idea how antidepressants really work,” and “The success rate with antidepressants is no greater today than when they first entered the mainstream 50 years ago.” Dr. Krystal further adds a discouraging note about “the lack of success in using … [the impressive accomplishments of] neuroscience to develop new treatments for patients with psychiatric illnesses. This lack of success reverberates in our society. Pharmaceutical companies are pulling out of psychiatric drug development.”

Light therapy

Light therapy was first demonstrated for winter depression (SAD) 30 years ago, but it is still seen as a new kid on the block, psychiatrically speaking. It has received lots of pop attention — largely as a self-treatment alternative. But it has received little attention from the medical field, which is still quite steeped in the Pharma model. A dedicated group of clinical researchers has, however, put in immense creative effort to explore the underpinnings of light therapy and its application to depressive disorders beyond SAD. Consider the very promising results of clinical trials for nonseasonal major depressive disorder, the depressed phase of bipolar disorder, depression during pregnancy, premenstrual depression, and depression during old age. These include some of the most serious cases, including drug-resistant cases. But they also include cases of moderate depression, which are far more frequent. Sometimes there has been partial improvement under light therapy, but in others complete remission without residual symptoms. Of course, there have been non-responders. Partial response and non-response to light therapy may just be a fact of life, as it is with antidepressant meds. But in some cases it may be due to suboptimal dosing of light intensity, spectral balance, field of illumination, duration of the treatment sessions, and treatment time of day relative to the patient’s circadian clock. This is new mental health technology, and it has to be mastered.

Beyond its successes in alleviating depression, light therapy has an “innocuous” side-effect profile compared with antidepressant drugs. That word, “innocuous,” comes from Frederick Goodwin, M.D., former director of the National Institute of Mental Health. Most common — and usually easily controlled by dose reduction — are queasiness (short of nausea) and physical agitation (can’t sit still). Mild headache may occur during the first few sessions, but this generally dissipates. Rarely have patients had to discontinue light therapy because of such side effects. Light therapy, as a natural energizer, needs to be dosed conservatively for patients with bipolar disorder, who may need to be using a mood stabilizer, such as lithium, to guard against switching high. (The same is true for antidepressant meds.)

It seems obvious at this point, especially if meds haven’t served you well, to try light therapy with your doctor’s knowledge, endorsement, monitoring — and, hopefully, supervision. Since many doctors have yet to learn about the technical dosing factors, you may need to inspire them to read up on the topic in a psychiatry handbook just about to be published. You can also get a nontechnical boost from our book for the general public.

Either/or, or both?

If you have a history of seasonal or nonseasonal depression, we can guess that you have already tried meds. You are probably still taking them even with persistent residual symptoms. But you’d like to see if you could do better. Switch to light therapy? No way! With very few exceptions, light therapy is compatible with antidepressant meds, so don’t stop them and risk worsening or relapse. Rather, add light therapy to your current regimen, and test whether it provides significant improvement. In a way, it’s like adding a second (or third…) medication, because light therapy has an active antidepressant effect. Only after you test it should you consider tapering or discontinuing your meds, and testing whether light therapy can do the job on its own, as it has for many others. Or… you may be “anti-drug,” refusing antidepressants or wishing you could get off them. If you are medication-free but suffering, the improvement under light therapy can be startling. Testimonials are not our style — if you pick and choose, you’ll always find a grateful patient — but the positive feedback we’ve gotten over the years has been our major incentive to pursue this work. It’s time to share this success in general clinical practice.