Major depression can be very hard to treat. Antidepressant medication can take several weeks to kick in, and not everyone responds favorably to current drugs. An anesthetic called ketamine that has been on the market since the early 1970s has been used experimentally to alleviate depression in patients who don’t respond to other therapy. The results are sometimes evident within hours of intravenous administration.
A new study in the journal Nature gives some hint of how the drug may be working. The research in mice found that the behavioral effects of a single dose of ketamine could be measured within half an hour. They lasted about a week. Studies of the rodents’ brains showed that the treated mice had increased levels of brain-derived nerve-growth factor. This discovery may lead to better antidepressant medications that work faster and more effectively than existing drugs.