Updated

A new antidepressant is now available that adds a very powerful weapon to those I can use to fight major depression.

Viibryd, just recently distributed to pharmacies, causes far fewer sexual side effects than most other new-generation antidepressants, but is at least as effective.

Viibryd’s mechanism of action mimics that of fluoxetine (Prozac) and sertraline (Zoloft) in one way. It prevents brain cells from reabsorbing the calming, uplifting brain chemical messenger serotonin after they release it—a process known as “reuptake.” With reuptake blocked, more of the serotonin lingers in the fluid-filled spaces between brain cells called synapses.

But Viibryd does something more than Prozac or Zoloft. It also mimics serotonin at some of the brain’s receptors for that chemical messenger. And this two-fold effect—blocking the reuptake of serotonin and also acting a like bit like serotonin at some receptors—has been helping some of my patients a great deal.

The use of antidepressants has been criticized of late, as large-scale scientific trials have raised doubts on whether they are much better than placebos. But I would caution those who would conclude that that means that the medications—especially the newest of the group—have no value for them. Studies are blunt instruments hat enroll hundreds of thousands of individuals who meet general criteria for major depression and then randomly assign them to get either a sugar pill or a real antidepressant. They don’t incorporate a psychiatrist’s experience and judgment as to which of his or her patients are actually the best candidates for medication, or which patients are most likely to benefit from which agents.

In my practice, for instance, the patients I treat with medicine are those who aren’t able to benefit fully from insight-oriented or cognitive psychotherapy (because the low mood or anxiety or inability to concentrate so typical of depression is preventing it) or those who have a history of responding to an antidepressant. No research study can replicate this selection process.

Nor, of course, could any research study replicate the process of taking an antidepressant while receiving psychotherapy from the doctor who prescribed it. That healing synergy escapes any attempt to quantify it.

Much of psychiatry is not cut and dry. Continuing a journey toward understanding one’s life, with the very same person who is constantly monitoring the effectiveness of the antidepressant he prescribed, is a complex interpersonal, neurochemical dance that no researcher can replicate.

While Viibryd does have a lower likelihood of causing sexual side effects or weight gain, it does have the potential to cause transient nausea and other GI side effects. And, of course, you should review all the possible side effects with your doctor. Also, always take Viibryd with some food. It needs to be digested with food in order to be properly absorbed.