The NHS has issued a reminder that patients taking amlodipine, a common blood pressure medication, should avoid eating grapefruit or drinking grapefruit juice. This warning comes as temperatures rise across the UK, prompting many to reach for refreshing fruits. Amlodipine is prescribed to approximately one in three UK adults with high blood pressure, accounting for nearly 35 million prescriptions annually.
Why Grapefruit Is Dangerous with Amlodipine
According to Harvard Health, grapefruit contains compounds that block the enzyme CYP3A4 in the liver and gut, which normally breaks down amlodipine. This can cause the drug to build up to unsafe levels in the bloodstream, increasing the risk of side effects such as excessive dizziness, flushing, or dangerously low blood pressure. The NHS states on its website: "Do not eat grapefruit or drink grapefruit juice while taking amlodipine because it can increase the chance of side effects."
Common Side Effects of Amlodipine
While not everyone experiences side effects, common ones include swelling in the ankles, feet, and legs (oedema), headaches, dizziness, sleepiness, a fast heartbeat or palpitations, facial flushing, tummy pain, nausea, constipation, diarrhoea, and fatigue. The NHS advises patients to consult a pharmacist or doctor if side effects are troublesome or persistent.
Serious but Rare Side Effects
The NHS notes that amlodipine can sometimes cause serious side effects, though these are rare. These include allergic reactions (anaphylaxis), inflammation of the pancreas (acute pancreatitis), and Stevens-Johnson syndrome—a severe skin condition with blistering, painful sores, and flu-like symptoms. In very rare cases, amlodipine can cause heart attacks. Patients experiencing serious side effects should contact NHS 111 immediately.
