The NHS has issued a warning to millions of people in the UK taking certain medications, including statins and amlodipine, to avoid grapefruit and its juice. The health service states that mixing these fruits with the drugs can lead to severe side effects by dangerously increasing the amount of medication in the bloodstream.
Statins, commonly prescribed to lower cholesterol, work by reducing the liver's production of cholesterol, thereby preventing fatty plaque buildup in arteries. Amlodipine, a calcium channel blocker sold under the brand name Istin, is used to treat high blood pressure and reduce the risk of heart attacks and strokes.
The NHS advises that patients on amlodipine should not consume grapefruit juice, as it can raise the level of the drug in the body and worsen side effects. This warning also applies to other medications, including some statins and anti-anxiety tablets, due to the fruit's ability to inhibit enzymes and transporters like CYP3A4 and P-gp, which are responsible for breaking down and moving drugs into the bloodstream.
Other citrus fruits, such as Seville oranges, pomelos, and limes, may also interact with these medications. The NHS recommends avoiding grapefruit entirely during the course of treatment unless a GP advises otherwise. Patients are urged to read medication labels and consult their doctor or pharmacist for guidance.
