Celebrities seem to have it all. Yet, there's often a dark hole in that charmed life that nothing is able to fill.

Ketamine may represent an effective adjunct therapy in the treatment of suicidal ideation in patients with major depressive disorder (MDD), according to the results of a randomized clinical trial published in the American Journal of Psychiatry.

A doctor said she was astonished by how well ketamine helps patients suffering from depression.

Existing treatments for PTSD are only moderately effective. Researchers hope ketamine will offer longer-term relief.

When you hear about ketamine, you may associate it with being an illegal party drug that causes vivid hallucinations. But it's also a powerful anesthetic, listed on the World Health Organisation's list of essential medicines.

"If you have patients that are likely to seriously injure themselves or kill themselves within a short period of time, and they've tried the standard treatments, how do you not offer this treatment?"