Grapefruit, Seville Oranges, Tangelos, Bergamot and Medication Interactions

Key Point:

Grapefruit severely alters the effectiveness of many medications (including very common cholesterol medications and very important heart medications) so grapefruit should be listed explicitly in the ingredients on cocktail menus. 

Background:

According to the United States FDA [link]

• While it can be part of a balanced and nutritious diet, grapefruit can have serious consequences when taken with certain medications. Currently, there are more than fifty prescription and over-the-counter drugs known to the U.S. Food and Drug Administration that can have negative interactions with grapefruit.
• As little as one cup of juice or two grapefruit wedges can alter the way your medicines work. When taken with medicine, grapefruit can delay, decrease, or enhance absorption of certain drugs; as a result, the patient does not receive the prescribed dosage of the medication.
• Seville oranges (often used to make orange marmalade) and tangelos (a cross between tangerines and grapefruit) affect the same enzyme as grapefruit juice, so avoid these fruits as well if your medicine interacts with grapefruit juice.

Bergamot oranges can also impact medications similarly. 

Drug Interactions:

Wikipedia offers a detailed page on grapefruit-drug interactions. [link]

Menu Labelling: 

Some bars use a "citrus mix" or simply specify "citrus" when they're using a combination of citrus fruits. Other bars, including some tiki bars using traditional "mysterious" cocktail descriptions, may not list some or any ingredients on their menus. 

But because of its interaction with very common medications, grapefruit is best explicitly listed on cocktail menus so that people avoiding it are properly informed. 

Possible alternatives to listing grapefruit among the ingredients include listing a symbol or asterix on the menu with a key at the bottom that could say something along the lines of "Contains grapefruit."  

Further Reading:

"Grapefruit Juice and Some Drugs Don't Mix" United States FDA [link]

"Grapefruit-drug interactions." Wikipedia [link]