Grapefruit juice

Grapefruit juice is the juice from grapefruits. It is rich in Vitamin C and ranges from sweet-tart to very sour. Variations include white grapefruit, pink grapefruit and ruby red grapefruit juice.

Grapefruit juice is important in medicine because of its interactions with many common drugs including caffeine and medications, which can alter how they behave in the body.

Grapefruit and grapefruit juice have been found to interact with numerous drugs, in many cases resulting in adverse effects. This happens in two ways: one is that grapefruit can block an enzyme which metabolizes medication, and if the drug is not metabolized, then the level of the drug in the blood can become too high leading to an adverse effect; the other effect is that grapefruit can block the absorption of drugs in the intestine, and if the drug is not absorbed, then not enough of it is in the blood to have a therapeutic effect.

One whole grapefruit or a glass of 200 mL (6.8 US fl oz) of grapefruit juice can cause drug overdose toxicity. Drugs which are incompatible with grapefruit are typically labeled on the container or package insert. People taking drugs can ask their health care provider or pharmacist questions about grapefruit/drug interactions.

Grapefruit juice is used in several cocktail,s such as the sea breeze (which consists of grapefruit juice, vodka, and cranberry juice); the salty dog, and the grapefruit mimosa.

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