This is the 3656th article of Da Medical Care
Grapefruit is "poisonous"?
yes!
Although grapefruit is delicious, if not eaten properly, it will have toxic side effects on the human body. Grapefruit is also known as grapefruit. Delicious and juicy grapefruit, many people love to eat. Drinking a cup of grapefruit juice every day can keep blood vessels healthy and help people stay away from cardiovascular disease, mainly because citrus fruits such as grapefruit are rich in flavonoids, which are good for cardiovascular disease. However, you should not eat grapefruit when taking certain drugs, otherwise there will be serious adverse consequences. Grapefruit contains the chemical components naringin, furancoumarins and flavonoid citrus, which inhibit the drug metabolism enzyme CYP3A4 in the human body, so that the time of staying in the body of the drug that is eaten is prolonged, resulting in an increase in the concentration of the drug in the blood. The half-life of the above ingredients in grapefruit juice is about 12 hours, that is, after 12 hours, the effect of grapefruit juice on the human body can be reduced to half. When drinking a cup of grapefruit juice, its effect is enough to last for 3 days. We can understand that drug overdose can produce toxicity, but often ignore the interaction between drugs and food, especially in this seasonal grapefruit market season, there are studies that show that the dose of 1 cup of grapefruit juice + 1 pill is sometimes equivalent to taking 20 tablets of the same drug! This is not alarmist!
The human body has a very important metabolic enzyme - P450 enzyme, eat into the food and drugs for metabolism, after decomposition, metabolism through the P450 enzyme into non-toxic substances excreted, this enzyme is a super-genetic family, there are many typings, including CYP3A4, CYP2C19, CYP2A6, CYP 2B6, CYP 2C8, CYP 2C9, CYP 2D6, etc., grapefruit in addition to delicious also contains many active ingredients such as furan coumarin, naringin, Bergamot, etc., can just inhibit the activity of the metabolic enzyme P450 enzyme CYP3A4 in the body, resulting in the drug can not be timely decomposed, metabolized, excreted from the body, resulting in the drug can not be metabolized in the body but accumulated in the human body, the amount of drug exceeds the amount of poisoning and death.
Studies have shown that most drugs react with certain components in grapefruit, resulting in an increase in the amount of some drugs entering the bloodstream. When the concentration of drugs in the blood exceeds the safe range, the harmfulness of drug side effects and adverse reactions to the human body also increases. In 1989, Bailey discovered that grapefruit juice can increase the bioavailability of drugs such as phillipidine, known as the "grapefruit juice effect.". A large number of current literature also reports the interaction of grapefruit with drugs acting on a variety of systems. In addition to increasing the blood concentration of the drug, studies have shown that grapefruit juice also causes a decrease in the absorbed dose of some drugs, such as the anti-allergic drug fexofenadine.
What medications cannot be taken with grapefruit?
1. Do not take lipid-lowering drugs with grapefruit
If grapefruit is taken during the period of taking lipid-lowering drugs such as atorvastatin, lovastatin, and simvastatin, the likelihood of muscle pain and rhabdomyolysis increases, and acute renal failure may occur in severe cases.
Clinical observations have found that patients with hyperlipidemia take a piece of lovastatin with a cup of grapefruit juice, and the result is equivalent to taking 12 to 15 tablets of lovastatin with a cup of water for hypolipidemic effects, and patients will have muscle pain and even kidney disease.
2. Do not take antihypertensive drugs with grapefruit
Because grapefruit itself also has antihypertensive effect, plus it can also increase the blood sample concentration of antihypertensive drugs, eating grapefruit or drinking grapefruit juice during taking nifedipine, nimodipine, verapamil and other antihypertensive drugs, just like overdose, so that blood pressure drops sharply, light cause dizziness, palpitation, fatigue, heavy induce angina, myocardial infarction or stroke.
At present, the antihypertensive drugs reported in the literature that have obvious interactions with grapefruit juice are mainly dihydropyridine calcium antagonists, such as felodipine and nifedipine. Therefore, not all types of antihypertensive drugs can not be taken with grapefruit.
3. Do not take sedative sleeping pills with grapefruit
Grapefruit can increase the likelihood of diazepam (diazepam), midazolam and other drugs causing dizziness and drowsiness, especially during the medication of high-altitude workers and drivers.
4. Do not take the contraceptive pill with grapefruit
Articles circulating on the Internet say that if a woman who has taken the pill eats 1 to 2 grapefruits after sex, or directly takes the contraceptive pill with a large cup of grapefruit juice before, then she may become a mother, because the grapefruit hinders women's absorption of contraceptives. In fact, this statement is wrong, in fact, the result is just the opposite. At present, the commercially available oral contraceptives for women are mainly steroid hormone drugs, and the main components contained in them are ethinyl estradiol, norethindrone, deoxypregesten and so on are CYP3A4 substrates. These drugs are catabolized by the metabolic enzyme CYP3A4. If eaten with grapefruit or grapefruit juice, the furocoumarin in grapefruit inhibits the production of CYP3A4 in the human body, which increases the blood concentration of the contraceptive pill, and the efficacy and toxic side effects will also be enhanced.
5. Do not take cardiotoxic drugs with grapefruit
Drugs with cardiotoxicity, such as the antibacterial drugs erythromycin and moxifloxacin, gastrointestinal motility drugs cisapride and domperidone, antiallergic drugs terfenadine, etc., should not be taken with grapefruit, otherwise it may cause dizziness, palpitations, arrhythmias and other symptoms, and even life-threatening.
6. Do not take immunosuppressants with grapefruit
Grapefruit can increase the blood concentration of immunosuppressants such as cyclosporine and increase liver and kidney toxicity. If such drugs are eaten with fruits such as grapefruit for a long time, there is a risk of tumor induction.
It is worth noting that with the deepening of food processing, many beverages, pastries and other foods also contain grapefruit juice or pulp ingredients, we should also pay attention to the ingredient list when purchasing, to avoid its interaction with drugs, if necessary, consult a doctor or pharmacist.
bibliography
1.Seden, Dickinson, Khoo, et al. Grapefruit-drug interactions. Drugs. 2010; 70(18): 2373-407.
2.Hanley, Cancalon, Widmer, et al. The Effect of Grapefruit Juice on Drug Disposition. Expert Opin Drug Metab Toxicol. 2011; 7(3): 267-86.
3.Cristóbal-Luna, lvarez-González, Madrigal-Bujaidar, et al. Grapefruit and Its Biomedical, Antigenotoxic and Chemopreventive Properties. Food Chem Toxicol. 2018; 112: 224-34.
4. Xin Huawen. CYP3A4 and P glycoprotein are disposed of in the intestine with drugs. Chinese Clinical Pharmacology and Therapeutics. 2005; 10: 721-5.
Author: The First Affiliated Hospital of Zhejiang University of Traditional Chinese Medicine
Lu Jiani Wrote
Governance Wang Jianping audit