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The Dangers of Mixing Aspirin and Acetaminophen (Tylenol)


I'm a thirty-something writer who lives in downtown Toronto. I've been an online writer for over seven years, focusing on health trends.

Consistently taking high doses of Tylenol and aspirin is dangerous to your liver and stomach.

Consistently taking high doses of Tylenol and aspirin is dangerous to your liver and stomach.

There is nothing worse than being struck by a debilitating headache in the middle of your day when you still have a million things to accomplish. Throbbing pain around or behind the eyes, or along the sides of the head, makes it difficult to focus, so you reach for the aspirin to relieve the pain.

When a headache makes it impossible to endure the light, sound, and activity of everyday life, we may be tempted to take more than just a couple of aspirin. So, what do we do? We pop two Tylenol (acetaminophen) and go about our day.

Everyone does it, so it must be safe, right? Unfortunately, mixing over-the-counter medications can have lasting and damaging affects on our internal organs.

Let's discuss the dangers of mixing aspirin and acetaminophen.

Is It Dangerous to Mix Aspirin and Acetaminophen?

Mixing these two medications can be dangerous. The short answer is to not overdo it. Taking the manufacturer's recommended dosage of aspirin and acetaminophen together for a short time has not been shown to cause organ damage. Aspirin and acetaminophen can be taken alone at higher doses without causing damage. So if you need long-term pain relief use either acetaminophen or aspirin, but not both, unless you are under a doctor's care.

Why Is It Dangerous to Take Too Many Aspirin and Tylenol?

  • Aspirin can cause dangerous bleeding in the stomach and intestines.
  • Drugs called NSAIDs, which include ibuprofen (Advil and generics) and naproxen (Aleve and generics), can magnify the risk of internal bleeding.
  • Ibuprofen might interfere with aspirin's ability to prevent heart attacks and strokes.
  • Use acetaminophen with caution. It can damage the liver, which is a terrible risk for people with cirrhosis of the liver or hepatitis, heavy drinkers, and seniors.
  • Don't take more than the maximum daily amount of 4,000 mg per day, or the equivalent of eight extra-strength 500 mg capsules.

Unless you have other medical conditions, particularly liver (risk with heavy drinks, hepatitis patents or seniors) or kidney issues (seniors are at risk here too), it is safe to mix acetaminophen and aspirin together for a short time, provided one does not go over the maximum dose for the two drugs.

— Alam Hallan RPh, CDE

Taking too many aspirin and Tylenol capsules can cause pains, such as liver damage and internal bleeding from the stomach.

Taking too many aspirin and Tylenol capsules can cause pains, such as liver damage and internal bleeding from the stomach.

Kidney Damage From Combining Aspirin and Tylenol

We have all reached for the aspirin after a night of drinking or when we have a bad headache. It happens to be the number one over-the-counter drug of choice for university and college students, not to mention being touted as a life-saver for anyone with heart problems. However, longterm mixing of acetaminophen (the ingredient in Tylenol) and aspirin can result in renal (kidney) damage. It will not happen if you mix them once or twice, but mixing repeatedly over a long period of time is dangerous.

Tylenol Causes the Formation of Free Oxide Radicals

Tylenol causes the formation of free oxide radicals which damage tissues, especially in the kidneys and liver. This is not a normal reaction to low doses of Tylenol, with but habitual use, especially at a higher dose, can begin damaging the innermost part of the kidney.

The kidneys perform two important functions: filtering waste from our internal fluids and producing hormones that help other organs to function. With repeated exposure to acetaminophen, the kidneys' structural units, the nephron limbs, thicken. This causes the kidneys to slowly lose their filtering capacity.

The Function of Nephrons in Your Body

The function of nephrons is to regulate the concentration of water and sodium salts in your body. They filter our blood, reabsorbing what is needed and disposing of the rest as urine. There are 800,000 to 1.5 million nephrons in each one of our kidneys. Together they eradicate waste, regulate our blood volume and blood pressure, control our levels of electrolytes and metabolites, and regulate the PH balance of our blood. This is what makes our kidneys such vital organs.

Are you clutching your blankets in fear? Don't worry. This damage is caused by long-term mixing of aspirin and acetaminophen. Do not make a habit of combining them. If you are experiencing pain that strong or debilitating, you should see your doctor. They can prescribe a medication strong enough to manage your pain.

Tylenol (acetaminophen) rapid-release capsules.

Tylenol (acetaminophen) rapid-release capsules.

Side Effects of Aspirin

All medications come with a certain amount of risk. Aspirin is no exception. While most side effects associated with aspirin are fairly mild, others are terribly painful. Stop using this medication and call your doctor at once if you have any of the side effects below.

The most common side effects include:

  • Upset stomach
  • Heartburn
  • Drowsiness
  • Headaches

Less common side effects include:

  • Black, bloody, or tarry stools
  • Coughing up blood or vomit that looks like coffee grounds
  • Severe nausea, vomiting, or stomach pain
  • Fever lasting longer than three days
  • Swelling, or pain lasting longer than 10 days
  • Hearing problems, ringing in your ears

Side Effects of Tylenol

Tylenol (acetaminophen) is an analgesic (pain reliever) and antipyretic (fever reducer) used for treating pain and fever associated with several conditions. Tylenol is available in generic form and over-the-counter (OTC). Both forms have the same side effects. While these side effects are usually mild, they should not be taken lightly.

Side effects of Tylenol include:

  • Nausea
  • Stomach pain
  • Loss of appetite
  • Itching
  • Rash
  • Headache
  • Dark urine
  • Clay-colored stools
  • Jaundice (yellowing of skin or eyes)

Side effects caused by an allergic reaction include:

  • Rash
  • Itching/swelling (especially of the face/tongue/throat)
  • Severe dizziness
  • Trouble breathing.

Frequently Asked Questions About Aspirin and Acetaminophen

Are Aspirin and Acetaminophen the Same?

There are essentially two types of OTC pain relievers. Some contain acetaminophen, which is processed in the liver. Other pain relievers contain non-steroidal anti-inflammatory drugs (NSAIDs). These are processed elsewhere. Examples of OTC NSAIDs are aspirin, ibuprofen (Advil) and naproxen sodium (Aleve).

Are Tylenol and Acetaminophen the Same?

Acetaminophen is the generic name for the brand name medication Tylenol, made by McNeil Consumer. Acetaminophen is a pain reliever for mild to moderate pain, such as headaches, muscle aches, backache, and toothaches, and fevers.

Can Anti-Inflammatory Drugs Thin Your Blood?

Tylenol (acetaminophen) is usually safe. Excessive acetaminophen can cause liver failure. Also, stay away from ibuprofen and aspirin-like anti-inflammatory drugs (NSAIDs) because these drugs can reduce amniotic fluid and thin the blood.

Is Acetaminophen Bad for Your Liver?

Acetaminophen is a very safe drug when taken as directed, even for people with liver disease. Nevertheless, every drug carries risks. Liver damage from acetaminophen, which can be severe, can result either from an overdose, or from regular doses that are taken while drinking alcohol.

What Are the Signs of Liver Damage From Tylenol?

You may mistake early symptoms of liver damage (for example, loss of appetite, nausea, and vomiting) for something else, like the flu. Liver damage can develop into liver failure or death over several days. Acetaminophen is generally safe when taken as directed.

How Much Is Too Much Acetaminophen?

The maximum daily dose for a healthy adult who weighs at least 150 pounds is 4,000 milligrams (mg). However, in some people, taking the maximum daily dose for extended periods can seriously damage the liver. It's best to take the lowest dose necessary and stay closer to 3,000 mg per day as your maximum dose.

Which Is Safer, Aspirin or Tylenol?

Acetaminophen is just not a very good pain reliever, yet it's the go-to drug because it's thought to be safe in low doses. However, aspirin is safer than acetaminophen, but to be used as a pain reliever, it requires much higher doses. These high doses can have side effects, such as an upset stomach.

For most common acute pain issues, these drugs are not the best choice. When it comes to pain relief, Ibuprofen is probably the best.

— Alam Hallan RPh, CDE

Alternatives to Taking Aspirin or Tylenol

ProductHow It Helps


Ginger is a powerful anti-inflammatory.


This distinctive, curry spice possesses anti-inflammatory properties.


Harvested from chili peppers, this remedy reduces nerve, muscle and joint pain by stopping the chemical known as substance P.


Magnesium supplements can help curb the pain of migraines.


Often called "Indian frankincense," boswellia contains active components like resin that reduce inflammation and pain.

Facts About Aspirin

  • Aspirin is found to be an effective treatment for pain, fever and inflammation.
  • An estimated 100 billion tablets are swallowed every year.
  • The most active ingredient in aspirin is acetyl salicylic acid, a derivative of a compound naturally found in plants, most notably the willow tree.
  • Hippocrates, the Greek physician, recommended that women in childbirth sip a brew made from the leaves of a willow tree to help treat labour pains.
  • In the 1970s, aspirin was shown to block a natural enzyme needed for production of natural hormones involved in many body processes, like pain and tissue injury.
  • Even today, the full effect aspirin has on the body is still being discovered.

Facts About Tylenol (Acetaminophen)

  • Tylenol is often recommended as a gastric-friendly alternative to aspirin, which has a history of irritating the stomach when taken without food.
  • It is one of the most widely used medicines in the United States, mainly for treatment of pain and fever.
  • In 2008, there were nearly 24.6 billion doses sold in North America.
  • Is the most common over-the-counter medication sited in unintentional, and intentional, overdoses, which can lead to acetaminophen-induced hepatotoxicity.
  • The risk of fatal liver damage is heightened by alcohol consumption. Even normal doses can cause this rare reaction.
  • Tylenol was first marketed in the United States, in 1953, by Sterling-Winthrop Co.
  • An active ingredient in Tylenol, paracetamol, is extremely toxic to cats and even the most minute portion can be fatal.


This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.


Norma Subialdea on February 03, 2019:

My brother recently was assaulted resulting him being in a coma. He has since been discharged and still has brain bleeding. He takes 81mg daily, as well as Tylenol 500mg for his headaches daily. He is experiencing severe headaches so he's taking Tylenol frequently through the day.

I think this is too much aspirin, because of his brain bleed.

He is 59 and takes the 81mg of aspirin daily for his heart.

Linux O'Beardly on December 31, 2018:

This is literally #FakeNews. Yes, you should always be careful with your consumption of OTC pain meds. In excess, Tylenol (acetaminophen) can absolutely destroy your kidneys. However, migraine specific pain relievers are a combination of acetaminophen, aspirin, and caffeine. That means the exact thing you're warning about here is sold in an over-the-counter combination. I found this page via Google looking for actual differences in the efficacy of acetaminophen versus aspirin and found this trove of misinformation. I trained as a nurse, my wife is a nurse practitioner, and I can say without question that this column is nothing more than click-bait conjecture. Reader beware. Please consult an actual professional and not this psuedo-science pile of horse manure.

KellyMediaBest from Tampa, Florida on September 26, 2012:

My mother has been a nurse at Children's Hospital all my life. Any ache or pain I've ever had, she's told me to take 3 Ibuprofen. She insists that Ibuprofen is the best pain reliever on the market. As I'm getting older, I'm taking steps everyday to make me healthier so that I don't have to use any medication (I drink a lot of water as well as green tea, exercise and consume a lot of fruits and veggies). Usually, there are plenty of ways that mother nature can ensure your overall health.

Dr Funom Makama from Europe on June 15, 2012:

Well written my friend.

hisandhers from Toronto, Ontario, Canada on May 20, 2012:

This is so true! People are so quick to just pop a pill anytime something goes slightly wrong so who knows how many times we have inadvertently double-dosed on something we shouldn't have?

Working in a pharmacy for many years dispensing medication has taught me you should always do your research before mixing any types of medication. I don't think you need to be a trained medical professional to write a Hub about that!

Stu (author) from Canada on May 14, 2012:

@Justaguest I certainly did not profess to be a trained healthcare professional, but this hub was written after a talk with my doctor. It was more about the longterm damage of abusing OTC medications and exceeding the maximum dosage regularly. Nowhere did I state these effects would happen overnight. But I appreciate your feedback.

Justaguest on May 14, 2012:

I can see why you are stressing people be careful about using OTC pain relievers because too much or one or the wrong combination of several can be dangerous and damaging to certain organs. It is very true that people take these products too often without realizing the potential side effects. People should always check with their doctor, pharmacist, or other healthcare professional before taking any OTC products.

BUT, telling people it is dangerous to mix acetaminophen and aspirin is NOT ACCURATE. The two products work differently and cause no harm to otherwise healthy people, as long as you do not exceed the maximum daily dose of either and do not mix them with alcohol. It worries me that people are taking that statement at face value, when it's not correct.

Please be careful what sources you use when giving medical advice online, especially if you are not a trained healthcare professional.

kelleyward on May 10, 2012:

Thanks for sharing this information because there can be a potentially life threatening consequence of mixing Tylenol and Aspirin. I get nose bleeds every time I take Aspirin so I use non-pharmacological methods to get rid of my aches and pains. Thanks for sharing, Take care, Kelley

Marlene Bertrand from USA on May 10, 2012:

I really enjoyed reading all this information about aspirin and Tylenol. One thing you made clear is that it is the "habitual" long-term mixing that causes the problem. Once, I had a doctor who prescribed alternate dosing of aspirin and Tylenol. I thought he must have been trying to kill me, but I did what he suggested and everything worked out fine. The fun facts are really quite interesting. You may not be a doctor, but a doctor couldn't have said it more clear than you just did. Very nice hub.

Simone Haruko Smith from San Francisco on May 10, 2012:

Whoah... someone might have told me about this a while ago, but they certainly did not go into depth and I had completely forgotten about it until reading your Hub! I'm so glad you wrote this.

Kaili Bisson from Canada on May 10, 2012:

Voted up and useful...thank you for sharing. As someone who has experienced a stomach ulcer from using pain meds, I learned the hard way about these "innocent" over the counter drugs, especially aspirin and NSAIDS.

Stu (author) from Canada on May 10, 2012:

@TDAPharm I really enjoyed your comment, I chose my topic after talking to my doctor about during a routine appointment. I found a wealth information citing the dangers of mixing the two drugs, so my hub was just a combination of the handful of articles I had read. I am not a pharmacist or expert or doctor or really a tylenol user but thought it would be interesting to write about. Thanks for the information.

@Denise Handlon Thanks for the hublove!

@lilyfly Your words are always SO nice and always make me smile, thank you! It would be truly a shame to no longer read your beautiful poetry. I think Disney took over our minds somewhere in the early nineties, whenever people started singing the songs in the shower, every morning.

@bryanbaldwin Thanks for the king words!

@Arlene V. Poma I thought it was strange too but, apparently, my doctor said it is two of the most common over-the-counter medications mixed. I prefer to just wait out the headache or, if I am able, lay down and wait for it to pass - I only reach for meds if the headache turns into a migraine. My sister is a habitual tylenol popper.

@Digby Adams I'm sure the ice pack and a cup of coffee is somewhat safer, thanks for stopping by!

Denise Handlon from North Carolina on May 10, 2012:

Excellent hub topic. Well written-rated up/U/I

TDAPharm from Massachusetts on May 10, 2012:

I want to make a few comments, and I apologize if it is lengthy.

Tylenol/paracetamol/acetaminophen/APAP is metabolized via the liver where it is conjugated to inactive metabolites (will not do anything)and then excreted via the urine. However, the liver can metabolize around 4g of Tylenol a day. Above that, Tylenol builds up and can cause liver damage. However, when drinking, your liver cannot metabolize as fast either, so Tylenol with alcohol in your system is dangerous as well because you may not be able to break down as much Tylenol as you normally would. As such, drinking and Tylenol is not recommended (at least if you have alcohol in your system still) due to potential liver damage. There is no real harm to the kidneys.

Aspirin, Ibuprofen, Naproxen, NSAIDs are dangerous to you when drinking because they can increase the risk of bleeding if you are imbibing too much of both. Aspirin has a higher likelihood of leading to bleeding as it has a greater anti-platelet effect (think about baby aspirin given to people at risk for cardiovascular disease so they dont make a clot) than the NSAIDs. Also, they are dangerous to your kidneys as well, as they can slow the flow of fluids to your kidneys. This can cause the kidney to become damaged and develop acute kidney failure. This is further a issue when drinking, due to the fact that most people drinking tend to urinate more (due to alcohols effect on anti-diuretic hormone = more urination) and thus can become dehydrated. This decrease in fluid volume in the blood coupled with Aspirin/NSAIDs ability to slow flow into the kidney is what can make it dangerous.

As for the combination of the two drugs, there is no real interaction between the two that is harmful (people with chronic pain and other disease may take both daily). Excedrin for instance has both. What comes into play is that the body needs to metabolize and excrete these drugs as well. When drinking, this can be a huge issue. If you treat your hangover the next day, it may help, but use a lower dose and dont slam yourself. And never pre-medicate the night before you go out. IT is always about how much a person takes and how much their body can handle. The dose makes the poison.

Lillian K. Staats from Wasilla, Alaska on May 10, 2012:

Janikon, you deserve a larger audience. This was tautly written, concise, and proffessional, and don't let the ****ards forget it. I wrote an off-color poem, and the "Christians" no longer read my stuff. Mercy of God. Prols.You know I'm going to write a poem about it. When did Disney take over emotions anyhow? Keep writing. Writers, good writers, will see it, and appreciate it.

bryanbaldwin from Los Angeles on May 09, 2012:

This is why I love checking hub pages. Informative stuff I wouldn't ever normally think of. Thanks for the info.

Arlene V. Poma on May 09, 2012:

It bothers me to watch people pop aspirin and Tylenol like candy. I won't use the stuff unless I absolutely have to. Even then, I will usually avoid it. I find it very strange that anyone would combine the two.

DigbyAdams on May 09, 2012:

Excellent summary of the perils of using and combining these two drugs. I'm not able to take either one of these at the moment (or ibuprofen or aleve). So all I get to use for a headache is a cup of coffee and an ice pack now.

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