Eating grapefruit or drinking grapefruit juice can affect some medicines. In most cases, it increases the level of the medicine in your blood. This can increase the risk of side effects or alter the effect the medicine has.
If your usual diet includes grapefruit or grapefruit juice and you've been prescribed a medicine that's affected by grapefruit, speak to your GP or pharmacist. Do not stop taking your medication without advice.
Some medicines affected by grapefruit are listed below, although there may be others that are not mentioned.
Medicines affected by grapefruit
Statins are medicines that lower your cholesterol. Grapefruit or grapefruit juice affects some statins.
Do not drink grapefruit juice if you're taking simvastatin. Grapefruit juice increases the level of simvastatin in your blood and makes side effects more likely.
Atorvastatin interacts with grapefruit juice if you drink large quantities (more than 1.2 litres daily), but an occasional glass is thought to be safe.
Currently, healthcare professionals advise it is safe to drink grapefruit juice and eat grapefruit if you're taking other types of statins.
Calcium channel blockers
Calcium channel blockers are medicines that relax the muscles that make up the walls of your arteries. They're used as part of the treatment of conditions such as high blood pressure (hypertension) and coronary heart disease.
Grapefruit juice interacts with some calcium channel blockers and increases the level of the medicine in your blood. If you're taking any of the medicines below, seek advice from your pharmacist or doctor if you wish to include grapefruit or grapefruit juice in your diet.
Grapefruit juice does not affect diltiazem.
Ciclosporin and immunosuppressants
Ciclosporin, sirolimus and tacrolimus are medicines that moderate your immune system (the body's natural defence system).
If you're taking any of these medicines, do not drink grapefruit juice without consulting your doctor.
Entocort is a medicine that contains budesonide and is used to treat Crohn's disease, a condition that affects the digestive system.
Do not eat grapefruit or drink grapefruit juice while you're taking this medicine, as the level of budesonide in your blood will increase.
Some medicines used in the treatment of cancers may interact with grapefruit juice. You should check with your doctor before drinking grapefruit juice.
This list is not exhaustive and there are a number of other drugs that may interact with grapefruit. The risk of experiencing the effect of a drug interaction as a result of grapefruit can vary a lot from person to person.
For more information check the patient information leaflet that comes with your medicine, or you can ask your pharmacist or GP or call NHS 111 for advice.
Read the answers to more questions about medicines.