So let's say you're really depressed and haven't been able to pull yourself out of your misery. You somehow find the energy to see a doctor and she gives you a prescription for an antidepressant. Then you find out the drug will take about four to six weeks to work, if it works at all.
Depression is a wicked condition that weighs heavy on the lives of millions of Americans—about one in ten, in fact. Antidepressants help, as do and other forms of therapy—such as "talk" therapies (e.g., counseling, psychotherapy). But the problem is time. People who are depressed need help now, not two months from now.
In other words, what the world could really use is a drug that eases depression quickly. Thankfully, that's one of the most interesting areas of research in mental-healthcare. Scientists say that in the not-too-distant future they'll be able to develop a so-called "fast-acting" antidepressant that works in a matter of days, not weeks or months.
Two existing drugs—ketamine and scopolamine—have become the major focus of research efforts at the National Institute of Mental Health (NIMH). In addition to the delay in seeing benefits from most antidepressants, "it's not unusual for someone to need a combination of therapies," before experiencing relief from the worst of their symptoms, Maura Furey, a scientist at the NIMH, told TakePart.
A major study on the effectiveness of antidepressants found that only about 30 percent of people saw their symptoms dissipate after an average of seven weeks on their first antidepressant. Many others continue dealing with the effects of depression four to six months after beginning treatment. "[Finding] something that could work overnight or in a few days would have a potentially huge impact," she says.
Scientists discovered the drug ketamine could snap some people with major depression out of their illness in a matter of hours.
The idea of a fast-acting antidepressant first emerged more than a decade ago when scientists discovered the drug ketamine could snap some depressed people out of their illness in a matter of hours. Ketamine is an anesthetic, mostly used in animals, that targets receptors in the brain known as NDMA.
However, the drug is not currently fit for therapeutic use in people. It causes hallucinations, disorientation, and amnesia. Researchers have since tried to create a drug like ketamine but without the side effects. A study published last year in the journal Science examined a ketamine-like drug called AZD6765 and found that 18 percent of people who took the medication had a full remission of their depression, lasting two days, compared to ten percent of those taking a placebo.
Furey says that scopolamine—best known as a motion sickness treatment—may have more potential as a fast-acting antidepressant. In 2006, Furey and her colleagues discovered its anti-depressive benefits. Unlike ketamine, scopolamine works through the brain's acetylcholine chemical messenger system, which plays a role in memory and how information is processed. The NIMH team's research showed that by blocking receptors for acetylcholine on neurons, scopolamine could lift depression in many patients within a few days.
"One important thing," notes Furey, "is that it doesn't work for everybody. But when it works, it works very quickly." Scopolamine has some side effects, like drowsiness and dry mouth. Moreover, there’s some negative Internet buzz about the drug. The side effects of scopolamine aren't bad, Furey says, "but it doesn't have a great reputation. There are some people who claim it has been used in date-rape type of stuff, which I haven't seen. It makes people a little bit nervous, which I understand."
There are also questions about how scopolamine, or any fast-acting antidepressant, would be used in the real world. If the drug works within a day or so, how long would therapy need to last? What are the chances that the depression would return after the medication is stopped? "We don't know how feasible it is to use these medications to treat people," Furey says. "How do we design a treatment protocol to work long-term? That has not been evaluated yet."
Still, the research so far is illuminating some fascinating things about the nature of depression. For example, depressed patients have a well-known tendency to process and remember negative emotions. The researchers suggest this tendency emerges from dysfunction in the acetylcholine system of the brain in some patients. In a recent study, Furey and her colleagues found that a boost of activity in the brain occurring when the brain is processing emotional information predicted who would respond to scopolamine.
This brain-activity test could be used to predict how people will respond to depression treatments, Furey says.
The study also suggests that researchers should consider designing antidepressants that work on the acetylcholinergic system of the brain. Modern antidepressants work on the serotonin or norephinephrine systems of the brain.
It may take at least five more years for a fast-acting antidepressant to reach the marketplace, but in the meantime, some people are using scopolamine off-label—something that is not advisable, Furey says. "We're not encouraging people to use it on their own," she stresses. "People call me telling me they are using it. And some physicians are prescribing it off-label. But I think that makes most physicians uncomfortable."
Would you try a fast-acting antidepressant? Have you had success with existing antidepressant? Did you need to wait to see benefits and/or adjust your dosage or try other drugs?
Shari Roan is an award-winning health writer based in Southern California. She is the author of three books on health and science subjects.