Researchers at the National Institutes of Health (NIH) say that a novel drug has been found to reduce symptoms of depression within three days of the first administration, though it generally takes three to four weeks for conventional antidepressant treatments to become effective.
The discovery of treatments with a more rapid onset is a major goal of biological psychiatry. The first drug found to produce rapid improvement in mood was the NMDA glutamate receptor antagonist, ketamine.
In the new study, another medication, scopolamine, was found to produce replicable rapid improvement in mood.
Scopolamine temporarily blocks the muscarinic cholinergic receptor, thought to be overactive in people suffering from depression.
For the study, Drs. Wayne Drevets and Maura Furey recruited outpatients with major depressive disorder who were randomly assigned to receive placebo and then scopolamine treatment, or vice versa, in a double-blinded design so that neither the researchers nor the patients knew which treatment they were receiving.
"Scopolamine was found to reduce symptoms of depression within three days of the first administration. In fact, participants reported that they experienced relief from their symptoms by the morning after the first administration of drug," Dr. Furey said.
"Moreover, one-half of participants experienced full symptom remission by the end of the treatment period. Finally, participants remained well during a subsequent placebo period, indicating that the antidepressant effects persist for at least two weeks in the absence of further treatment," Dr. Furey added.
The study has been published in the new issue of Biological Psychiatry.