Now it is autumn, a variety of fruits have been on the market, a fruit called “grapefruit”, many people like to eat. This fruit is called the “ruby of fruits” and is rich in nutrients. But for some patients with high blood pressure and heart disease, this fruit can have some effects with their regular medication, affecting the effect of the drug, and there is a potential risk for related diseases. So what ingredients does grapefruit contain that can interact with medications and what types of medications can grapefruit affect? Let’s talk to you. First let you see what grapefruit is like: most drugs metabolism need to go through the liver, and will use a special enzyme CYP3A4, many drugs are broken down by CYP3A4, metabolism, and excretion of the body. And grapefruit juice contains a variety of active ingredients such as furanocoumarins, naringenin, bergamotin, citrusin, can very clearly inhibit the activity of CYP3A4. So once you drink a lot of grapefruit juice, it will affect the action of this metabolic enzyme, the body will slow down the rate of decomposition of drugs, eaten drugs stay in the body for a longer period of time, resulting in an increase in the concentration of drugs in the blood. And when the concentration exceeds the drug treatment, the effect may be counterproductive, or even cause drug poisoning. Heart patients should pay particular attention to the effects of grapefruit juice on drugs, such as: antihypertensive drugs in the calcium ion antagonist, which is our common “diphenhydramine” type of antihypertensive drugs. If you eat grapefruit or drink grapefruit juice during medication, it is equivalent to an increase in the amount of medication, which may cause a sudden drop in blood pressure, and in serious cases, may also induce angina, myocardial infarction or stroke. Another medicine to note is the anti-arrhythmic drugs, such as verapamil, amiodarone, quinidine, etc.. Cardiotoxicity may occur when grapefruit is eaten while taking medication. It further leads to the risk of malignant arrhythmias and even increases the possibility of sudden death in elderly high-risk patients. Lipid-lowering drugs should also be noted. Especially for patients with coronary heart disease often take statin drugs, simvastatin, atorvastatin, etc. Grapefruit or grapefruit juice, can cause the drug to accumulate in the body, increasing the risk of liver damage, rhabdomyolysis and other adverse reactions. However, the drug Rosuvastatin is not affected by this. Also some patients with atrial fibrillation take long-term oral anticoagulants, such as warfarin and rivaroxaban. These drugs may also increase the anticoagulant effect when taken together with grapefruit juice. The result of this action is that some serious bleeding occurs, even life-threatening. How long before and after taking medications should I not drink grapefruit juice? For most people, it takes 72 hours to fully recover the inhibited CYP3A4 function after consuming grapefruit juice, which means avoiding practical grapefruit for 72 hours before and 24 hours after taking the medication. Therefore, if you need to take hypertension, lipid-lowering and other chronic disease medication every day, we recommend that you do not eat grapefruit. Are there any problems with other types of grapefruit besides grapefruit? Studies have shown that other types of grapefruit, which contain similar ingredients, do not have the same effect as grapefruit, but should be consumed with caution.