Comparing Acetaminophen and Aspirin

Both Reduce Pain and Fever but Work Differently

Medically reviewed by Lindsay Cook, PharmD

Aspirin and Tylenol (acetaminophen) are both pain and fever relievers. However, they differ in their drug class and the way they work.

This article will clarify the differences between aspirin and acetaminophen.

<p>PixelsEffect / Getty Images</p> Female taking tablet with glass of fresh water

PixelsEffect / Getty Images

Female taking tablet with glass of fresh water

What’s Acetaminophen Used For?

Tylenol (acetaminophen) is an over-the-counter (OTC) drug (medication not requiring a prescription) to ease pain and lower fever. It also relieves minor aches and pains due to the following:

  • Menstrual pain

  • Headache

  • Backache

  • Arthritis

  • Toothache

Can Children Take Acetaminophen?

Yes, Tylenol (acetaminophen) can treat pain and reduce fever in children. However, a child's weight and age determine the proper dosage.

How Does Acetaminophen Work?

Tylenol's (acetaminophen's) mechanism of action (how it works) is not entirely known.

However, it is believed to block prostaglandin production, a chemical in the brain that causes fever, pain, and inflammation.

It also helps control and lower fever by affecting a specific part of the brain that regulates body temperature called the hypothalamus.

Is Acetaminophen an Anti-inflammatory?

No.

Tylenol (acetaminophen) effectively helps reduce pain and fever.

However, acetaminophen is not an anti-inflammatory medication like nonsteroidal anti-inflammatory drugs (NSAIDs) such as the following:

  • Aspirin

  • Aleve (naproxen)

  • Advil or Motrin (ibuprofen)

Is Acetaminophen an NSAID?

No. Tylenol (acetaminophen) is not considered an NSAID.

Although acetaminophen and NSAIDs like aspirin are frequently used to relieve pain and lower fever, they belong to different drug classes and work differently.

Does Acetaminophen Reduce Swelling?

No. Tylenol (acetaminophen) is mainly used to reduce pain and fever but not swelling.

Your healthcare provider may recommend NSAIDs like ibuprofen or naproxen to treat swelling.

Does Acetaminophen Thin Your Blood?

No. Tylenol (acetaminophen) is not an anticoagulant (blood thinner). Hence, it does not have blood-thinning properties.

Is Acetaminophen Good for Headaches?

Yes. Tylenol (acetaminophen) is a frequently recommended and used OTC medicine for mild to moderate headaches, including tension headaches.

Does Acetaminophen Reduce Fevers?

Yes. Tylenol (acetaminophen) is commonly used to reduce fever in infants and adults.

What’s Aspirin Used For?

Aspirin, also known as acetylsalicylic acid, is used for several purposes, including the following:

  • Relieves pain

  • Lowers fever and inflammation

  • Prevents heart attack and stroke



Warning About Using Aspirin in Children

Aspirin use is linked with a higher risk of Reye's syndrome, a rare but life-threatening condition in viral infections. Due to this increased risk of Reye's syndrome, do not give aspirin to children or young adults having symptoms of or who have been diagnosed with viral infections, like chicken pox or the flu.



How Does Aspirin Work?

Aspirin relieves pain and swelling by blocking the production of prostaglandins, certain chemicals that are known to increase pain, inflammation, and fever. It also reduces the risk of clot formation in blood vessels by stopping blood platelets from clustering to prevent heart attacks or strokes.

Is Aspirin an Anti-inflammatory?

Yes. Aspirin is an anti-inflammatory medication used to reduce swelling or inflammation.

Is Aspirin An NSAID?

Yes. Aspirin is an NSAID commonly used to decrease inflammation, relieve pain, and lower fever.

Does Aspirin Reduce Swelling?

Yes. Aspirin is known for its anti-inflammatory activities. It can help reduce swelling, mainly when the swelling is due to inflammation.

Does Aspirin Thin Your Blood?

Yes. Aspirin has blood-thinning properties, preventing platelets from clumping together and forming blood clots.

Is Aspirin Good for Headaches?

Yes. Aspirin is an analgesic (pain-relieving) drug used to relieve different types of pain, including headaches.

Does Aspirin Reduce Fevers?

Yes. Aspirin has antipyretic (fever-lowering) properties. Hence, it can be used to reduce and control fevers.

When to Take Aspirin or Acetaminophen

When choosing between aspirin and Tylenol (acetaminophen), your healthcare provider will advise you on which medication to take based on factors such as your:

  • Medical history

  • Current symptoms

  • Potential medication interactions

When to take aspirin:

  • Lowering fever: Aspirin is used to lower elevated body temperature due to infection or inflammation.

  • Pain and inflammation relief: Aspirin helps to relieve pain and reduce swelling due to its non-steroidal anti-inflammatory properties.

  • Blood thinning: Healthcare professionals may prescribe 81 milligrams (mg) of low-dose aspirin (sometimes called baby aspirin) to high-risk people to reduce the risk of cardiovascular events like heart attacks and strokes.

  • Tension and migraine headaches: Aspirin can be used to treat migraines and tension headaches.

  • Preeclampsia: During pregnancy, your healthcare provider may sometimes prescribe aspirin to help prevent preeclampsia, a pregnancy complication with symptoms like increased blood pressure.

  • History of liver toxicity: People with liver problems may benefit from using aspirin instead of acetaminophen to reduce the risks of liver damage.

When to take Tylenol (acetaminophen):

  • Lowering fever: Acetaminophen effectively decreases fever due to infection.

  • Pain relief (no inflammation): Acetaminophen is used mainly for relieving mild to moderate pain, including muscle aches and pains.

  • History of ulcers or stomach bleeds: Acetaminophen is often preferred for those with stomach sensitivity or ulcers due to being gentler on the stomach than NSAIDs like aspirin.

  • Use in children: Acetaminophen is a preferred choice for reducing fever and pain in children. It is especially recommended to avoid the use of aspirin for conditions like the flu or chicken pox due to the risk of Reye's syndrome.

Can You Take Aspirin and Acetaminophen Together?

You may take aspirin and Tylenol (acetaminophen) together on certain occasions only as directed by your healthcare provider.

However, get professional advice from your medical provider before taking these two medicines at the same time.

Although combining both medicines can help improve fever and pain control, it may also increase the risk of side effects.

Do Other Common Medications Contain Aspirin and Acetaminophen?

Many OTC and prescription drugs contain aspirin or Tylenol (acetaminophen). Hence, taking them with either aspirin or acetaminophen may have additive effects, increasing the potency of the drugs and causing more side effects.

Please tell your healthcare provider and pharmacist about all the medicines you take.

Some common medicines that contain aspirin include:

  • Aggrenox (aspirin/extended-release dipyridamole)

  • Alka-Seltzer

  • Excedrin

  • Fiorinal (aspirin/butalbital/caffeine)

  • BC powder

Some common medicines that contain acetaminophen include:

  • Percocet

  • Excedrin

  • Alka-Seltzer products

  • Tylenol with codeine

  • Fioricet (butalbital/acetaminophen/caffeine)

  • Norco (hydrocodone/acetaminophen)

Is Aspirin or Acetaminophen Safer?

Aspirin and Tylenol (acetaminophen) are generally safe when used as directed.

However, each medication has side effects.

The safety of each can depend on various factors like the following:

  • Your medical history

  • Health conditions

  • Other medications (including supplements) you may be taking

Side Effects & Precautions

Aspirin and Tylenol (acetaminophen) are considered safe and effective. However, each medication has its side effects and precautions for certain populations.

The most common side effect of aspirin is stomach discomfort. Other side effects common to both drugs are nausea, indigestion, and rash.

Rash, swelling, and difficulty breathing are all signs of severe side effects with Tylenol (acetaminophen). Seek immediate medical attention if you experience severe side effects from your medications.

Population

Avoid aspirin

Avoid acetaminophen

Children and teens

Yes, due to the increased risk of Reye’s syndrome

No

People on blood thinners

Yes

No

People with bleeding disorders or ulcers

Yes

No

People with liver issues

No

Yes

Pregnant people in the third trimester

Yes

No

Allergic to NSAIDs

Yes

No

Acetaminophen allergy

No

Yes



Explainer

Try taking NSAIDs like aspirin with food or milk to reduce gastrointestinal (stomach) side effects.



Interactions for Aspirin and Acetaminophen

Various OTC and prescription drugs contain aspirin and Tylenol (acetaminophen), which can interact with many other medications.

Please consult your healthcare provider before taking any new prescriptions, OTC medications, or supplements.

Drug interaction

Aspirin

Acetaminophen

Alcohol

Yes, increased risk of bleeding

Yes, this may lead to increased liver toxicity

Anticoagulants (blood thinners)

Yes, increased risk of bleeding

Yes, especially long-term use of oral acetaminophen 4,000 mg/day increases the international normalized ratio (INR) in people on the drug warfarin

NSAIDS

Yes, increased risk of bleed and stomach sensitivity

No

Corticosteroids

Yes, increased risk of stomach discomfort

No

Isoniazid

No

Possible increase in liver damage

Summary

While Tylenol (acetaminophen) and aspirin are great at relieving pain or lowering fever, they may not be suitable for everyone.

Your choice of medicine will depend on factors like your medical history, allergies, and more.

Always consult your healthcare provider before starting any new medicine.

Frequently Asked Questions

When should I take aspirin vs. acetaminophen?

You can consider taking aspirin if you're experiencing inflammation and need relief. However, if you're allergic to NSAIDs or if aspirin causes stomach discomfort, then acetaminophen may be a better option. Although Tylenol (acetaminophen) doesn't help with inflammation, it is not harsh on your stomach and can be a safer choice in such cases.

When should I not take aspirin or acetaminophen?

Do not take aspirin or Tylenol (acetaminophen) without speaking to your healthcare provider if you are on blood thinners. Also, avoid these drugs if you are alcohol dependent, as this may increase the risk of liver damage and stomach bleeding.

Can children take aspirin?

A rare but potentially fatal health condition, Reye's syndrome, has happened in children and young adults on aspirin. Therefore, children should avoid aspirin due to the increased risk of this condition. Speak to your child's pediatrician if you need help selecting the most appropriate medication.

Read the original article on Verywell Health.