Q. Is ketamine ever prescribed for people with eating disorders? A parent of one of my patients asked about this recently. Isn’t this a drug primarily used by veterinarians? (BK, Sacramento, CA)
A. Ketamine is widely used as a short-acting anesthetic in veterinary medicine. However, it is increasingly used for patients with depression, and might help those with anorexia nervosa, according to a recent review by Dr. Anya Ragnhildst at Duke University, Durham, NC, and the University of Utah, Salt Lake City (Brain Sci. 2022. 12:382).
Ketamine was developed in the 1960s as a fast-acting alternative to phencyclidine, or PCP. At first it was used as an anesthetic, but now is used for treating refractory depression. In the beginning, this involved IV administration, often several times per week. When it is used for depression, two things have stood out: it often works for those not helped by other treatments and it works quickly, at times within hours (albeit with short-term effects).
At this point, only 5 case studies or small case series (about 20 people) involving use of ketamine have been reported, and these are summarized in the Brain Science review. Broadly, improvements in mood, anxiety, rigid thinking, and/or ED symptoms were seen in many who received ketamine.
These results are encouraging, but there are several caveats. First, these reports involved IV ketamine, but the FDA-approved version of the drug calls for intranasal administration—simpler to administer but probably less effective for those with depression. Second, while ketamine is well tolerated by those with depression, it is still unclear whether this is true for persons who have AN. Nevertheless, there is growing clinical interest in the use of ketamine, and this will undoubtedly include use in those with eating disorders, particularly when they have a combination of depression and AN.