A doctor is warning people taking common medications like statins and antidepressants that ingesting grapefruit can have serious consequences. Grapefruit contains natural compounds that inhibit an important enzyme called cytochrome P450 3A4, which plays a crucial role in breaking down oral medications.
How Grapefruit Interacts with Medications
When you ingest grapefruit, it blocks this enzyme, causing drugs that would normally be broken down in the gut wall to instead pass through intact, leading to significantly higher-than-intended blood levels of the medication. This can cause serious side effects, such as muscle breakdown and cramps in patients taking statins, and dizziness and low blood pressure in patients taking certain blood pressure medications.
Antidepressants like sertraline also come with a warning to avoid grapefruit. As little as one grapefruit or 200 milliliters of juice can cause a clinically relevant increase in medication concentrations, and the effect can last up to 72 hours because grapefruit irreversibly inactivates the CYP3A4 enzyme.
People should keep an eye on mixed fruit juices, smoothies, and cocktails that contain grapefruit juice. If a patient ingests a large amount of grapefruit while on these medications, they should monitor for any symptoms and avoid ingesting any more grapefruit.
Other Ingredients to Be Aware Of
The doctor also warns of other ingredients that patients should be aware of, such as vitamin K-containing ingredients, dairy-containing products, and herbal remedies that can inhibit or increase the activity of the CYP3A4 enzyme.
Original reporting: KTBS 3 (Shreveport) — read the source article.
