Why Antidepressants and Grapefruit Don't Mix

by Jerry Kennard, Ph.D. Medical Reviewer

The number of drugs that can be dangerous if taken alongside grapefruit or other citrus fruits is increasing rapidly. Although the interaction between grapefruit juice and various drugs have been known for some time concerns have been raised over the number of drugs now involved and the lack of general knowledge in the health community.

Very few people are able to recall a great deal of what their doctor says. Maybe this is due to anxiety, or the words used, the amount of information being imparted, or the state of mind the person is in. Then again, the doctor may simply forget to tell you that your breakfast grapefruit routine can increase the risk of side effects or alter the intended effect the medicine.

Writing in the Canadian Medical Journal, a team of researchers at the Lawson Health Research Institute in Canada, state the number of drugs known to have serious side effects with grapefruit has risen from 17 in 2008 to 43 in 2012.

James Gallagher, a health and science reporter for BBC News, has reported that grapefruit, grapefruit juice and other citrus fruits like Seville oranges and limes, have the same effect. Chemicals in grapefruit, he reports, wipe out the enzyme meant to break the drugs down. Too much of the drug escapes and what was intended as a therapeutic dose can potentially rise to toxic levels.

The antidepressant Sertraline (Zoloft) is amongst a list of widely prescribed medicines for the treatment of depression, anxiety or mood disorders. Others include buspirone (BuSpar), bupropion (Zyban), carbamazepine (Tegretol), clomipramine(Anafranil), diazepam (Valium), quetiapine fumarate (Seroquel), midazolam (Versed), trazodone (Desyrel), and triazolam (Halcion).

Dr. Carol Parker, a pharmacist and content manager for Drugsdb.com, says grapefruit can cause Sertraline to be absorbed at too fast a rate. This, she says, "can lead to an overdose and other side effects such as nausea, mood swings, agitation, itchy skin and dizziness." The effects may be particularly harmful in patients just starting with Sertraline.

The drug information sheet included with packs of Sertraline does include a statement regarding the interaction with grapefruit. Unfortunately this and related information is easily overlooked, perhaps due to the tiny print size, or simply the inability of the person with depression to concentrate or absorb the information properly. The Lawson researchers state that "Unless health care professionals are aware of the possibility that the adverse event they are seeing might have an origin in the recent addition of grapefruit to the patient's diet, it is very unlikely that they will investigate it."


Gallagher, J. (2012, November 26). Grapefruit and pills mix warning. BBC News/Health. Retrieved from http://www.bbc.co.uk/news/health-20497086

Okan, E. (2009) The Grapefruit Juice Effect: Psychopharmaceutical Drugs.


Jerry Kennard, Ph.D.
Meet Our Writer
Jerry Kennard, Ph.D.

Jerry Kennard, Ph.D., is a Chartered Psychologist and Associate Fellow of the British Psychological Society. Jerry’s work background is in mental health and, most recently, higher education. He is the author of various self-help books and is co-founder of positivityguides.net.