Ketamine is a compound commonly used for pain management or as an anaesthetic in medical and veterinary procedures, and is increasingly attracting interest as a potential treatment for mental health conditions such as severe depression and post-traumatic stress disorder.

While it's not entirely clear how it works in the brain, ketamine is known to block specialised receptors in the membranes of some nerve cells.

Does ketamine treat depression?

The complex consequences of this blockage produce a broad range of neurological and psychological effects, from a sense of mental detachment to sedation and memory loss.

Ketamine is relatively fast acting, with injections taking a few minutes to take effect and lasting up to half an hour. Ingested, its effects are typically felt within half an hour, with most therapeutic effects lasting just a few hours.

In 2019, the FDA approved a form of ketamine for use as a nasal spray to treat forms of depression that are resistant to other therapies.

Is ketamine illegal?

In many jurisdictions around the world, ketamine is a controlled substance that requires a medical authority to prescribe and safely administer.

The compound is also used illicitly as a recreational drug for its hallucinatory and pleasurable qualities, especially among rave and dance party communities, where it goes by alternative names such as special K, vitamin K, Kit Kat, and super acid.

In low doses the substance can produce euphoria, light-headedness, and a mild sense of removal from the surrounding environment. Higher doses can significantly interfere with movement, cause increasingly detached sensations (referred to colloquially as being in a 'k-hole'), and intense hallucinations.

What are the risks of taking ketamine?

In a medically supervised setting using known dosages, side effects of taking ketamine are relatively rare and minor, usually limited to psychotropic episodes such as hallucinations and anxiety, and occasionally short term cardiovascular stimulation such as elevated heart rates.

Most data on more severe health and psychological risks of ketamine use come from recreational settings.

Distributed as a white or off-white crystal, compressed into pills, or dissolved in a liquid, an unregulated form of ketamine can be confused or mixed with other materials and contain no consistent dose.

Short-term risks can include anxiety and a sense of panic, drowsiness, confusion, and nausea, with a low-mood 'come down' taking place after any euphoric effects have faded. Long-term effects can have an impact on other organs, such as the kidneys and bladder, where ulceration and incontinence isn't unheard of. There is also some evidence that excessive use can lead to dependency.

Deaths from illicit ketamine use are exceedingly rare and more commonly associated with combining the drug with other substances such as alcohol, and potentially even caffeine.

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