Many drugs have warnings indicating they should not be mixed with acetaminophen or Tylenol; these include leflunomide, teriflunomide, prilocaine, epinephrine and lidocaine, according to Drugs.com. There are a total of 14 major drug interactions that can occur in conjunction with acetaminophen.
Some drugs taken with acetaminophen can create serious health risks such as liver problems and methemoglobinemia, explains Drugs.com. Methemoglobinemia is a condition where the blood does not carry enough oxygen throughout the body and to the organs, resulting in nausea, headaches, fatigue, rapid heartbeat and shortness of breath. There are 60 drugs that, when combined with acetaminophen, can have moderate side effects, and there are 89 drugs with minor side effects.
Acetaminophen is a medication used to relieve pain; reduce fever; and treat headaches, muscle aches and colds, states Drugs.com. Those with liver disease or a history of alcohol abuse should avoid this drug as it can further harm the liver. Rarely does the medication cause certain side effects such as dark stools and urine, skin rash, unusual bruising, fatigue and yellow skin. Those who experience these side effects should consult a medical professional. If diarrhea, cramping, nausea, vomiting, swelling and pain accompany use of acetaminophen, contact emergency medical care immediately.