Researchers are always looking for new antidepressants since current methods are not putting all individuals with depression in remission. Approximately one third of patients with depression are resistant to current treatments. A recent proposal has been Ketamine aka Special K. Its mood altering properties are often enjoyed by club goers. Yes, it’s most commonly known as a street drug, but before you rule it out, note that is has been used in medicine safely for over 40 years! Veterinarians use Ketamine as a tranquilizer for cats and horses. Doctors use it in anesthesia during surgery. In fact, even dentists use it because it doesn’t have cardiac or respiratory effects. This is why dentists are able to put you under, without having all the equipment that a hospital has. Ketamine is commonly used in third world countries where medical monitoring equipment is in short supply. Something else that makes Ketamine safe is it’s half-life. This is how long the drug stays active in the body. Ketamine has a half-life of 3 hours, which is not long enough to cause any neurotoxicity. This is great, but it also means that the antidepressant effects will wear off as well.
A recent study showed that 71% of treatment-resistant bipolar sufferers responded to Ketamine. The primary side effects were mild dissociative symptoms, but this was only reported during infusion (first 40min.). A UK study found that participants who responded to Ketamine found relief within days after infusion. Days?! Can you imagine a treatment where you didn’t have wait a month or more just to find out if it works!? The same study reported the beneficial effects of Ketamine to last anywhere between 25 days and 8 months. A third study found Ketamine in the form of a nasal spray to be just as potent as intravenous administration. Researchers are also hoping that Ketamine could be a substitute for electroconvulsive therapy (ECT) which is usually used for those with treatment resistant depression. ECT has had some positive results, but memory loss has been reported as a side effect. This doesn’t happen with Ketamine.
Much of what we currently know about Ketamine is from its use in anesthesia. So we know a one-time dose has no detrimental effects, but what about long-term usage? It may be that the ability of the brain to process the drug decreases over time. Studies on Ketamine-dependent individuals show changes in white matter in the brain.
Ketamine has potential. I think it would be great if it were available as a medical rescue for people who come to the ER in crisis, but it has a long way to go before it’s ready for the market.