Mixing these drugs can be life-threatening, collect them now!

Some drugs cannot be mixed, otherwise it may endanger the patient's life. At the same time, many patients also have serious misunderstandings about medication, often not following the doctor's orders and taking medication on their own, leading to serious consequences. Therefore, we will take stock of those drugs that cannot be mixed. While clinicians have a deeper impression, they should also remind patients to pay attention to medication safety!

Roxithromycin + compound methoxyphenamine capsule = aminophylline poisoning

Compound methoxyphenamine capsules contain aminophylline, methoxyphenamine, narcotine, chlorpheniramine and other substances. Roxithromycin is a liver enzyme inhibitor, which can reduce the metabolism of aminophylline and significantly increase the blood concentration of aminophylline, leading to aminophylline poisoning. Therefore, after mixing the two drugs, patients may experience symptoms such as muscle tremors, tachycardia, and arrhythmia. In severe cases, they may even die from respiratory and cardiac arrest.

Special attention

1. Four types of Chinese patent medicines containing aminophylline: (1) Shunqi Huatan Granules (nigra, plantain, liquorice, aminophylline, chlorpheniramine maleate, etc.); (2) Zhubei Dingchuan Pills (pearl, Fritillaria cirrhosa, ephedra, aminophylline, promethazine hydrochloride, etc.); (3) Pingchuan Kangyan Capsules (bitter almond, platycodon, aminophylline, ammonium chloride, etc.); (4) Jiangdan Kechuan Tablets (pig bile powder, black plum meat, dried ginger, aminophylline, ammonium chloride, etc.).

2.4 Antimicrobial drugs that can cause aminophylline poisoning: (1) Macrolides (erythromycin, clarithromycin, roxithromycin, etc.); (2) Quinolones (norfloxacin, ofloxacin, ciprofloxacin, etc.); (3) Tetracyclines (minocycline, doxycycline, etc.); (4) Lincosamides (clindamycin, lincomycin, etc.).

3.2 Special antibacterial drugs: The interaction between azithromycin, moxifloxacin and aminophylline has no clinical significance and they can be used together.

Cold medicine + cold medicine = liver failure

At present, about 80% of the anti-cold medicines on the market contain acetaminophen, also known as paracetamol, which is a commonly used antipyretic and analgesic in clinical practice. Many patients have a misunderstanding of medication, thinking that drug stacking can make the disease get better faster, but excessive use of cold medicines containing acetaminophen may cause liver damage or even liver failure. Therefore, clinicians must remind patients that the interval between acetaminophen medications should be ≥4 hours, and no more than 4 times within 24 hours; the maximum daily dose for adults is 2 g, and the maximum dose for children is 15 mg/kg each time.

Special attention

These Chinese patent medicines contain acetaminophen: (1) Ganmaoling capsules and granules (acetaminophen, chlorpheniramine); (2) Jingan capsules (acetaminophen, amantadine, chlorpheniramine); (3) Ganmaoqing tablets, capsules and granules (acetaminophen, chlorpheniramine, morpholino); (4) Zaihua Ganmao tablets (acetaminophen, chlorpheniramine); (5) Wei C Yinqiao tablets and granules (acetaminophen, vitamin C, chlorpheniramine); (6) Xinfufang Daqing tablets (acetaminophen, amobarbital, caffeine, vitamin C); (7) Zhiganjia capsules (acetaminophen, morpholino, chlorpheniramine), etc.

Huoxiang Zhengqi Water + Cephalexin = Ethanol Poisoning

Huoxiang Zhengqi water contains alcohol, which will be digested in the body to produce acetaldehyde, which is then metabolized into acetic acid and eventually excreted from the body. Cephalosporins inhibit the metabolism of acetaldehyde in the body and produce a mutual reaction, which is clinically called the "disulfiram reaction", causing acetaldehyde to accumulate in the body and cause poisoning. Patients may experience symptoms such as nausea, vomiting, dizziness, and headache after taking the mixed medicine. In severe cases, they may also experience breathing difficulties and even threaten their lives. In addition, drugs that usually contain "tincture" in their names contain alcohol and cannot be taken at the same time as cephalosporins and metronidazole. Since ethanol and drugs have a process of metabolism in the body, people who drink alcohol should abstain from alcohol 2 days before taking the medicine and can only lift the ban after stopping the medicine for 7 days.

Special attention

1. Common drugs containing ethanol: cold cough syrup, Danhong Huayu oral liquid, Sophie cough syrup, Gynecological Baifeng oral liquid, Jinhoujian spray, Oulongma drops, L-carnitine oral liquid, cyclosporine A oral solution, etc.

2. Common drugs that can cause disulfiram-like reactions: cephalosporin antibiotics, metronidazole, tinidazole, secnidazole, glibenclamide, etc.

Iodine + mercurochrome = mercuric iodide poisoning

The iodine contained in iodine tincture will react with the mercury in mercurochrome to form mercuric iodide, which will be deposited on the surface of the skin. Mercury itself is toxic and can cause harm to the body.

Special attention

The main chemical component of cinnabar is mercuric sulfide, which reacts with bromine and iodide in the gastrointestinal tract to produce highly irritating mercuric bromide and mercuric iodide, thus leading to drug-induced enteritis.

1. Oral Chinese patent medicines containing cinnabar: Niuhuang Qingxin Pills, Angong Niuhuang Pills, Baizi Yangxin Pills, Anshen Yinao Pills, Bushen Yinao Pills, etc. cannot be used together with Western bromide and iodide drugs, such as tribromide mixture, Pasteur's mixture, potassium iodide mixture, compound iodine solution, etc.

2. Chinese patent medicines for external use containing cinnabar ingredients: Dieda Qilin Powder, Honghua Qilin Powder, Qilin Ointment, Zijin Tablet, Zijin Powder, Bingpeng Powder, Zhishang Ointment, Saimei'an Cream, etc. cannot be used with iodine-based disinfectants.

3. External Chinese patent medicines containing cinnabar, such as Jiedu Liyan Pills and Meihua Dianshe Pills, cannot be used together with iodine lozenges.

Sulfonamides + Vitamin C = Urinary stones

Vitamin C is an acidic substance, and sulfonamides and their metabolites are prone to form sulfonamide crystals in an acidic environment, which can form urinary stones and cause kidney damage. If the condition requires simultaneous use, the medications can be taken 2 hours apart.

Special attention

1. When vitamin C is used together with alkaline drugs, such as sodium bicarbonate, rhubarb, soda, aminophylline, etc., not only will vitamin C be decomposed and ineffective, but the alkaline drugs will also weaken their own pharmacological effects due to the neutralization effect.

2. Vitamin C has a strong reducing property and is easily oxidized. Copper ions and iron ions can accelerate the oxidation of vitamin C. Therefore, vitamin C should not be taken at the same time as drugs containing copper and iron ions to avoid affecting the efficacy of vitamin C.

3. In the case of iron deficiency, vitamin C can increase the absorption of iron. For example, taking vitamin C together with ferrous sulfate is beneficial to the absorption of ferrous sulfate.

Aspirin + Ginkgo Biloba = Bleeding

Ginkgo leaf capsules and ginkgo lozenges contain high levels of flavonoids and ginkgolides. Taking them with aspirin may increase the risk of bleeding. If you have just had surgery, the risk of bleeding is even higher. Ginkgo leaf preparations can competitively bind to the membrane receptors of platelet activating factor, antagonizing the effects of platelet activating factor, thereby inhibiting platelet aggregation and adhesion.

Special attention

1. Current research suggests that the combined use of ginkgo extract and low-dose aspirin does not increase the risk of bleeding.

2. When Ginkgo biloba preparations are used in combination with antiplatelet drugs or anticoagulants, patients should be advised to promptly inform their doctor if bleeding, bruising, new onset headaches, or visual changes occur.

Warfarin + acetaminophen = bleeding

Warfarin is a commonly used anticoagulant drug for patients with atrial fibrillation. Taking it simultaneously with acetaminophen increases the risk of gastrointestinal bleeding.

Special attention

Patients who need to take warfarin for a long time should closely monitor the international normalized ratio of coagulation 3 to 5 days after starting to take acetaminophen. If black stools, abdominal pain, or other discomfort occur, they should seek medical attention immediately.

Sildenafil + nitroglycerin = low blood pressure

Some patients with heart problems may have erectile dysfunction, and many patients often secretly take drugs such as sildenafil (commonly known as Viagra) for the sake of face. It should be noted that if this drug is taken before the onset of angina pectoris, and nitroglycerin tablets are taken at the same time, blood pressure may drop rapidly, which may even be life-threatening in severe cases.

Special attention

Clinicians must remind heart disease patients that if complications such as erectile dysfunction occur, they should take the initiative to go to the hospital to find the cause and receive regular treatment. If unexplained chest pain occurs, they should also go to the hospital for diagnosis and treatment immediately.

Antidiarrhea medicine + calcium supplement = blocked intestines

Drugs containing loperamide hydrochloride can effectively relieve diarrhea, but calcium supplements will make the stool hard. If the two are used together, it may cause gastrointestinal obstruction.

Special attention

After stopping diarrhea, take calcium supplements after a certain period of time to avoid conflict between the two ingredients. If you need to take these two medicines at the same time for treatment, you should consult a doctor to determine the interval between taking the medicines. If any abnormality occurs, you should stop taking the medicine and seek medical attention in time.

In clinical practice, not only will adverse reactions occur when drugs are mixed, but certain drugs and foods cannot be taken at the same time.

Antihypertensive drugs + grapefruit = sudden drop in blood pressure

1. Lipid-lowering statins, such as simvastatin, atorvastatin, lovastatin, etc., if you eat a lot of grapefruit or drink grapefruit juice while taking these drugs, the drugs will accumulate in the body, increasing the risk of adverse reactions such as liver damage and rhabdomyolysis, and even causing acute renal failure.

2. The health supplement red yeast rice contains statin analogs, so it is not advisable to eat grapefruit after taking the medicine.

3. Rosuvastatin is neither an inhibitor nor an enzyme inducer of cytochrome P450 isoenzymes, and grapefruit juice has not been found to have an effect on the pharmacokinetics of rosuvastatin.

4. Amlodipine: Drinking grapefruit juice has no significant effect on the pharmacokinetics of amlodipine, but some studies have shown that grapefruit juice can increase the blood concentration of amlodipine. Therefore, it is not recommended to consume grapefruit (juice) while taking amlodipine.

Honey + cold medicine = reduced efficacy

Cold medicines containing acetaminophen, when in contact with honey (honey is acidic, pH value is about 3.9), will cause the acetaminophen to hydrolyze, generating acetic acid and aminophenol, which will weaken the antipyretic effect. Similarly, Chinese patent medicines containing honey, such as cough syrups and Chuanbei loquat paste, should not be taken with the above-mentioned cold medicines.

It is unscientific to take cold medicine with honey. Cold medicine should be taken with warm water. If children are afraid of the bitter taste of the medicine, sugar can be used instead of honey to take it with water.

Reference: Remember the Deadly Medication Mix, 3rd Edition