Bjork’s typically oddball quote when she received the 1998 Brit Award was probably the last time this humble, tangy citrus fruit hit the headlines so, being an aficionado of the odd half from time to time, imagine my surprise to read that eating the fruit can have harmful effects on people taking medication. This is because, apparently, the grapefruit (and other varieties of citrus fruit) contains a group of chemicals called furanocoumarins which inhabit the stomach and inhibit the activation of certain drugs. So taking one of 43 types of prescription medicines at the same time as ingesting a grapefruit means that there is more of the active drug in the body than was intended, leading to potentially harmful side-effects. There is no escaping from these wretched furanocoumarins – they are present in all forms of grapefruit, whether in juice form, concentrate or the fruit itself.
For readers who either want to avoid this menace or to experiment with a new form of legal high, the list of drugs predicted to interact with grapefruit include
- Drugs used to treat cancer (crizotinib, dasatinib, erlotinib,everolimus, lapatinib, nilotinib, pazopanib, sunitinib, vandetanib, vemurafenib)
- Drugs used to treat or prevent infections (erythromycin, halofantrine, maraviroc, primaquine, quinine, rilpivirine)
- Drugs used to treat high cholesterol (atorvastatin, lovastatin, simvastatin)
- Drugs used to treat heart and blood vessel conditions (amiodarone, apixaban, clopidogrel, dronedarone, eplerenone, felodipine, nifedipine, quinidine, rivaroxaban, ticagrelor)
- Drugs affecting the central nervous system (oral alfentanil, buspirone, dextromethorphan, oral fentanyl, oral ketamine, lurasidone, oxycodone, pimozide, quetiapine, triazolam, ziprasidone)
- Drugs used to treat nausea (domperidone)
- Immunosuppressants (cyclosporine, everolimus, sirolimus, tacrolimus)
- Drugs used to treat urinary tract conditions (darifenacin, fesoterodine, solifenain, silodosin, tamsulosin)
Side-effects can include rapid heartbeat, complete heart block, kidney damage, blood clots and damage to bone marrow.
You have been warned!