Taking Acetaminophen or Tylenol for Back Pain

Searching for an over-the-counter medication for your back or neck pain? Tylenol, or acetaminophen, may be a possibility. Here are a few of the basics.

Woman with back pain
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Acetaminophen, the Active Ingredient

The active ingredient in Tylenol is acetaminophen. Categorized as an analgesic, acetaminophen is an over-the-counter medication used to relieve pain and reduce fever. Acetaminophen is found in many other pain medications besides Tylenol, including Excedrin, Vanquish, and Aspirin-Free Anacin. Acetaminophen is also available in generic form, as well as in combination with other drugs.

Acetaminophen is neither an opioid (i.e., narcotic pain reliever) nor an NSAID (anti-inflammatory.) Because of this, it may allow you to avoid side effects and/or complications that make other pain medicines impractical as choices. That said, acetaminophen does come with the risk of liver toxicity.

What It Does

Tylenol is used for short-term pain relief for mild to moderate pain, and to temporarily reduce fever. You might consider taking this medication for back or neck pain due to muscle ache and/or arthritis.

Even though acetaminophen is widely used, it may not relieve low back pain as well as you think. A 2015 review and meta-analysis published in the British Medical Journal found high-quality evidence that taking it does not result in lumbar spine pain relief.

How Tylenol Works for Back Pain

Tylenol affects the central nervous system. It works by reducing the amount of brain chemicals that excite pain signals. It also exerts a cooling effect by inhibiting the prostaglandins that play a role in the brain’s heat-regulating center.

Forms of Acetaminophen

Tylenol and acetaminophen come in tablet form. This includes extended release tablets, capsules, and liquid or drop form. You can take Tylenol with or without food. It also comes as a suppository.

Side Effects and Complications

The Tylenol label warns that taking acetaminophen can cause liver disease. Because of this, the label says, if you take more than 3 drinks every day you should talk to your healthcare provider about also taking acetaminophen.

The BMJ study mentioned above also found high-quality evidence that people who take paracetamol (which is another name for acetaminophen) every day are almost 4 times as likely to have abnormal liver function test results than those who took a placebo pill. Just the same, the authors say that the clinical relevance of the abnormal liver tests are unclear.

Allergy to acetaminophen and/or other ingredients in the medication is possible. If you have a known allergy to any of the ingredients listed on the box, don’t take this medication. If you're unsure, talk to your healthcare provider. And if you do have an allergic reaction after taking acetaminophen, seek medical attention immediately.

Health Conditions and Other Medications

If you take blood thinners (anticoagulants), for example Coumadin (warfarin), seizure medication, especially Tegretol (carbamazepine), Dilantin(phenytoin), or phenobarbital, phenothiazines, INH(isoniazid), or other pain, fever, or cough or cold medication, be sure to ask your healthcare provider if it is OK to also take Tylenol or other acetaminophen.

According to the Hepatitis C Project, the active ingredient in Tylenol, acetaminophen, can be found in approximately 200 other medications. As mentioned above, the range for a safe dosage of Tylenol is very narrow. This means that if you take more than one medication, it is essential to read the labels for each one of them to be sure that you are getting acetaminophen only once. The risk of overdose effects is amplified if you drink or have chronic alcoholism or other liver disease.


Many people store medications, including Tylenol, in their bathroom medicine chest, or in the kitchen, near the faucet. But to keep this medication in good working order, it is best to store it away from heat and moisture. Keep the pills in the bottle it came in, and make sure the bottle is tightly closed.

It is very important to keep Tylenol and other acetaminophen products away from a child’s reach, as taking it inappropriately can do irreparable harm.

If your Tylenol is outdated or you no longer need it, throw it away. But first, ask your pharmacist the proper way to do so.


Although it is widely used, Tylenol works in a very narrow margin of safety. If you take too much, your liver may become toxic very quickly. Unfortunately, the amount of Tylenol that causes liver toxicity is different from person to person, and some researchers think that problems can occur at the dosage amount listed on the label. This is especially true if you drink or have chronic alcoholism. If you are at all unsure how much Tylenol or acetaminophen to take, or if you should take it at all, ask your healthcare provider.

If your practitioner has you taking Tylenol regularly and you miss a dose, take as soon as you remember. But if it is almost time for the next dose, just wait. In any case, don’t double dose.

Over Dosage

Taken in proper doses, acetaminophen, the active ingredient in Tylenol utilizes a chemical “pathway” in the liver to break down the medication and metabolize it. When you take more than you should, the chemical pathway gets overwhelmed, as if there were too much “traffic” in the pathway. When this happens, medication molecules are rerouted to a different chemical pathway. The alternate route breaks the drug down differently than does the primary route; one of the big differences between the chemical pathways is that the alternate route creates toxic by-products that kill liver cells.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. NIH U.S. National Library of Medicine National Center for Biotechnology Information. Acetaminophen.

  2. Machado GC, Maher CG, Ferreira PH, et al. Efficacy and safety of paracetamol for spinal pain and osteoarthritis: systematic review and meta-analysis of randomised placebo controlled trials. BMJ. 2015;350:h1225. doi:10.1136/bmj.h1225

  3. MedlinePlus from NIH US National Library of Medicine. Acetaminophen.

  4. Mazaleuskaya LL, Sangkuhl K, Thorn CF, Fitzgerald GA, Altman RB, Klein TE. PharmGKB summary: pathways of acetaminophen metabolism at the therapeutic versus toxic doses. Pharmacogenet Genomics. 2015;25(8):416-26. doi:10.1097/FPC.0000000000000150

Additional Reading
  • Acetaminophen. Drugs.com. Jan 2008.
  • Acetaminophen. Medline Plus. Rumack, B. Acetaminophen misconceptions. Hepatology.

  • Kuffner, e. Dart, R. Bogdan, G., Hill, R. Casper, E. Darton, L. Effect of maximal daily doses of acetaminophen on the liver of alcoholic patients: a randomized, double-blind, placebo-controlled trial. Arch Intern Med

  • Kuffner, E. et al. The effect of acetaminophen (four grams a day for three consecutive days) on hepatic tests in alcoholic patients–a multicenter randomized study BMC Med. 2007 May 30;5:13.

  • Machado, G., PhD., et. al. Efficacy and safety of paracetamol for spinal pain and osteoarthritis: systematic review and meta-analysis of randomised placebo controlled trials. BMJ

  • Seirafi, M., Iten, A., Hadengue, A. Acetaminophen: hepatotoxicity at therapeutic doses and risk factors. Rev Med Suisse.

  • Van Mil, A., Janssens, A. Acetaminophen use by chronic alcohol abuser: a therapeutic dose may be too much for the liver. Ned Tijdschr Geneeskd.

  • Buck, M., Pharm D. FCCP, FPPAG. Intravenous Acetaminophen Use in Infants and Children. Medscape website.
  • Dart, R., Baily, E. Does therapeutic use of acetaminophen cause acute liver failure? Pharmacotherapy. 2007 Sep;27(9):1219-30.
  • Franciscus, A. Highleyman, L. Acetaminophen and Your Liver HCSP Fact Sheet. Hepitits C Support Project.
  • Larson, A. Clin Liver Dis. 2007 Aug;11(3):525-48, vi. Related Articles, Acetaminophen hepatotoxicity.
  • Polson J, Lee WM. AASLD position paper: the management of acute liver failure.
  • Teater, D., M.D., Evidence for the efficacy of pain medications. National Safety Council.

By Anne Asher, CPT
Anne Asher, ACE-certified personal trainer, health coach, and orthopedic exercise specialist, is a back and neck pain expert.