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Tylenol coffee: acetaminophen and caffeine | Cigna

Caffeine and acetaminophen don’t mix well

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Sep 27 2007

Consuming large amounts of caffeine while taking acetaminophen, one of the most widely used painkillers in the United States, could potentially cause liver damage, according to a preliminary laboratory study reported in the Oct. 15 print issue of ACS’ Chemical Research in Toxicology, a monthly journal.

The toxic interaction could occur not only from drinking caffeinated beverages while taking the painkiller but also from using large amounts of medications that intentionally combine caffeine and acetaminophen for the treatment of migraine headaches, menstrual discomfort and other conditions, the researchers say.

Health experts have warned for years that consuming excess alcohol while taking acetaminophen can trigger toxic interactions and cause liver damage and even death. However, this is the first time scientists have reported a potentially harmful interaction while taking the painkiller with caffeine, the researchers say.

While the studies are preliminary findings conducted in bacteria and laboratory animals, they suggest that consumers may want to limit caffeine intake — including energy drinks and strong coffee — while taking acetaminophen.

Chemist Sid Nelson, Ph.D., and colleagues, of the University of Washington in Seattle, tested the effects of acetaminophen and caffeine on E. coli bacteria genetically engineered to express a key human enzyme in the liver that detoxifies many prescription and nonprescription drugs. The researchers found that caffeine triples the amount of a toxic byproduct, N-acetyl-p-benzoquinone imine (NAPQI), that the enzyme produces while breaking down acetaminophen. This same toxin is responsible for liver damage and failure in toxic alcohol-acetaminophen interactions, they say.

In previous studies, the same researchers showed that high doses of caffeine can increase the severity of liver damage in rats with acetaminophen-induced liver damage, thus supporting the current finding.

“People should be informed about this potentially harmful interaction,” Nelson says. “The bottom line is that you don’t have to stop taking acetaminophen or stop taking caffeine products, but you do need to monitor your intake more carefully when taking them together, especially if you drink alcohol.”

Nelson points out that the bacteria used in the study were exposed to ‘megadoses’ of both acetaminophen and caffeine, much higher than most individuals would normally consume on a daily basis. Most people would similarly need to consume unusually high levels of these compounds together to have a dangerous effect, but the toxic threshold has not yet been determined, he says.

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Certain groups may be more vulnerable to the potentially toxic interaction than others, Nelson says. This includes people who take certain anti-epileptic medications, including carbamazepine and phenobarbital, and those who take St. John’s Wort, a popular herbal supplement. These products have been shown to boost levels of the enzyme that produces the toxic liver metabolite NAPQI, an effect that will likely be heightened when taking both acetaminophen and caffeine together, he says.

Likewise, people who drink a lot of alcohol may be at increased risk for the toxic interaction, Nelson says. That’s because alcohol can trigger the production of yet another liver enzyme that produces the liver toxin NAPQI. The risks are also higher for those who take large amounts of medications that combine both acetaminophen and caffeine, which are often used together as a remedy for migraine headaches, arthritis and other conditions.

The researchers are currently studying the mechanism by which this toxic interaction occurs and are considering human studies in the future, they say. The National Institutes of Health funded the initial animal and bacterial studies.


Posted in: Drug Trial News

Tags: Acetaminophen, Alcohol, Anti-Epileptic Drug, Arthritis, Bacteria, Caffeine, Coffee, Drugs, E. coli, Enzyme, Laboratory, Liver, Metabolite, Migraine, OCT, Painkiller, Research, Toxicology, Toxin

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Is It Safe To Drink Coffee While Taking Tylenol?


By Joanna Marie/

Whether you’re a die-hard coffee connoisseur or you simply enjoy a cup in the morning, there’s no denying that this warm, comforting liquid is an integral part of many people’s lives. According to 2023 survey data published by the National Coffee Association (NCA), over 65% of adults drink coffee daily, with the average person consuming around three cups per day. While coffee may seem like a simple and harmless drink, it’s important to note that it may interact with certain medications, like Tylenol.

Tylenol is a brand name for a popular over-the-counter pain reliever and fever reducer medication, also known by its generic name, acetaminophen, according to Healthline. It is widely used to treat mild to moderate pain, such as headaches, backaches, menstrual cramps, and fever, and is available in various forms, including tablets, capsules, chewable tablets, liquid, and granules. Tylenol works by blocking the production of prostaglandins, chemicals in the body that cause pain, per Tufts University. However, unlike nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and aspirin, Tylenol does not have anti-inflammatory properties. 

The safety of drinking coffee while taking Tylenol (acetaminophen) has been a topic of debate in the medical community for many years. While there is no clear consensus, some studies have examined the potential risks of combining these two substances.

Mixing coffee with Tylenol

ViDI Studio/Shutterstock

Coffee has many health benefits — the British Liver Trust even says that moderate amounts may help reduce the risk of liver disease. However, when combined with Tylenol, these beneficial effects are lost. According to a 2017 study published in the Journal of Drug Delivery and Therapeutics, one serious side effect of Tylenol is liver damage. This can occur if you take Tylenol for an extended period or if you take more than the recommended dose. The study adds that excessive coffee intake while using Tylenol correlates with an increase in damage to the liver, kidneys, and gastrointestinal system.

While there may be some potential risks associated with combining caffeine and Tylenol, a 2007 randomized controlled trial published in the journal Current Medical Research and Opinion found that safe amounts of both substances did not significantly impact the body. The researchers concluded that moderate coffee consumption is unlikely to affect the safety or efficacy of Tylenol. However, they did mention that caffeine enhances the efficacy of Tylenol.

In general, it may be best to follow proper dosage guidelines for caffeine and Tylenol and avoid excessive use of either substance — this is especially important if you have liver disease or other underlying health conditions. The recommended daily caffeine intake limit is about 400 mg daily for most adults, equivalent to about 4 cups of coffee, says the Mayo Clinic. For Tylenol, the maximum recommended daily dose is 4,000 milligrams (mg) for adults, and it is important not to exceed this amount (per Harvard Health Publishing). 

Side effects of Tylenol


Overall, Tylenol is a widely used and effective pain reliever and fever reducer that is available without a prescription. However, it is important to use it responsibly and to talk to a doctor if you have any concerns about taking Tylenol, whether with coffee or alone. They can help you determine the appropriate dosage and timing for both substances based on your health needs and medical history.

While Tylenol is generally considered safe when taken as directed, it can be harmful when taken in excessive amounts. Taking more than the recommended dose can lead to stomach pain, nausea, and vomiting, per MedlinePlus. Ironically, Tylenol can sometimes cause headaches as a side effect. According to the Mayo Clinic, this is known as medication overuse or rebound headaches — you can experience this if you take certain medications like Tylenol for an extended period. Other potential side effects of Tylenol include dizziness and tiredness, and in rare cases, it can also cause low blood sugar, as explained by DrugWatch. Some people may also experience allergic reactions to Tylenol, including rash, hives, difficulty breathing, itching, or facial or mouth swelling. If you experience any of these symptoms, seek medical attention immediately.

In addition, Tylenol can interact with certain medications, including blood thinners, according to Harvard Health Publishing. For this reason, it’s always best to speak to your doctor before combining medications.


The most scandalous cases when firms recalled their products

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In the pursuit of revenue, corporations lose millions of dollars, and customers lose their lives.

April 23, 20202

Just this year, the US Consumer Product Safety Commission asked customers to stop buying Panasonic laptops because their batteries caught fire; IKEA lamps, because their metal frames shock people; lights for bicycles that ignited while under the driver’s seat …

Companies often try to protect their customers. But not always.

Tylenol 1982

In the summer of 1982, there were seven cases of poisoning in Chicago with Tylenol, then the most popular pain reliever in the United States at the time. The first victim was a 12-year-old girl. After drinking the pill, she dropped dead after a few seconds. It turned out that the tablet contained 65 mg of cyanide (lethal dose – 5 mg!). Similar incidents occurred over the next two days in different parts of the city.

As you might guess, panic seized the city: people threw away their supplies of Tylenol, and sales in stores fell to zero. The management of Johnson & Johnson took unprecedented measures: they recalled the entire drug from pharmacies and stores, and this, so you understand, is about $ 100 million. As it turned out, the manufacturers were not to blame for anything: an anonymous poisoner was operating in Chicago, who poured poison into medicine packages, and then returned them to store shelves.

Johnson & Johnson developed a new way of packaging Tylenol: now under the cap of the vial, the neck was hermetically sealed with foil. Today it is the standard for pharmaceuticals. Tylenol has managed to regain its place in the drug market.

Firestone and Ford Explorer tires, 2000

In 2000, a scandal erupted in the United States when it became public knowledge that Ford Explorer SUVs rolled over on the roads much more often than other cars. In this case, we are talking only about cars equipped with original Firestone tires. The situation was aggravated by the fact that, as it turned out, both companies – Ford and Firestone – were aware of what was happening since 1996 years old, but made every effort not to correct technical errors, but to hush up the matter.

The number of victims in the USA alone exceeded one thousand people. When the secret became clear, every more or less self-respecting newspaper in the United States hastened to write a devastating, revealing article, their total number exceeded 5 thousand. Ford’s sales decreased by 80%, the company lost about $3 billion. Firestone has withdrawn about 3 million tires from sale.

Both companies, instead of paying compensation to the victims and their families, hastened to blame each other and got bogged down in lawsuits and litigations, some of which have not been completed to this day.

Chinese milk formulas and milk, 2008

In June 2008, a “melamine scandal” broke out in the world: a high content of melamine was found in the dairy products of a number of Chinese manufacturers – a substance that is essentially non-toxic (at least not more than than table salt), but at ultra-high concentration leading to kidney stones. It is commonly used in mineral fertilizers and plastics. Manufacturers added it so that when measured, the protein level in milk seemed higher (the milk itself was diluted with water). Two companies — Mengniu Dairy Group and Yili Industrial Group — added melamine to their milk (regular and powdered), infant formula, chocolate bars, instant coffee and cookies. Among other things, milk was supplied to schools and kindergartens. By the time the decision was made to recall the products, six children had died.

As a result, the Chinese authorities decided to seize all spoiled products (most of them were exported to the countries of the Pacific region). Even chicken eggs had to be seized, as melamine was added to chicken feed. 19 people – entrepreneurs and civil servants – were punished (up to life imprisonment). Two entrepreneurs, Jang Yuzhong and Geng Jinping, were shot dead in 2009.

Text author:Semyon Shraik

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