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KneeRelief Side Effects

Generic name: acetaminophen / caffeine / magnesium salicylate

Note: This document contains side effect information about acetaminophen / caffeine / magnesium salicylate. Some of the dosage forms listed on this page may not apply to the brand name KneeRelief.

Applies to acetaminophen / caffeine / magnesium salicylate: oral tablet

Warning

Do not give this medication to a child or teenager with a fever, flu symptoms, or chicken pox. Salicylates can cause Reye's syndrome, a serious and sometimes fatal condition in children.

Do not take more of this medication than is recommended. An overdose of acetaminophen can damage your liver or cause death. Call your doctor at once if you have nausea, pain in your upper stomach, itching, loss of appetite, dark urine, clay-colored stools, or jaundice (yellowing of your skin or eyes).

In rare cases, acetaminophen may cause a severe skin reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

In rare cases, acetaminophen may cause a severe skin reaction that can be fatal. This could occur even if you have taken acetaminophen in the past and had no reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling. If you have this type of reaction, you should never again take any medicine that contains acetaminophen.

Stop using this medicine and call your doctor at once if you have:

  • bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds;

  • easy bruising or bleeding; or

  • swelling, rapid weight gain, little or no urinating.

Common side effects may include:

  • upset stomach;

  • trouble sleeping (insomnia); or

  • feeling anxious or restless.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

More about KneeRelief (acetaminophen / caffeine / magnesium salicylate)

Consumer resources

Related treatment guides

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.