At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.
Common and minor side effects of acetaminophen can include fatigue, mild drowsiness, dry throat, and nausea. Some people may feel jittery and have problems falling asleep after taking it as well. These side effects are temporary and should disappear on their own within a few days. More serious side effects are often symptomatic of allergic reaction or liver damage, such as facial swelling, difficulty breathing or swallowing, yellow-tinted skin or eyes, and physical weakness or flu-like symptoms. Like any over-the-counter medication, acetaminophen should only be taken according to individual recommended dosages to minimize the chances of developing potential health risks that require medical attention.
Tylenol is one of the most popular medications containing acetaminophen. People may take it to help relieve pain from headaches, flu, arthritis, and minor injuries. While it is generally considered safe for short-term use, adults should not self-medicate with acetaminophen for more than 10 days without a physician's supervision. Since the liver metabolizes this drug, frequent alcohol use can increase the likelihood of developing side effects of acetaminophen. Physicians advise that consuming three or more alcoholic drinks per day while taking acetaminophen puts the average adult at risk for liver disease.
Additional side effects of acetaminophen concerning the liver are usually apparent within a short time frame. Anyone experiencing visible jaundice, decreased urination, abdominal pain, vomiting, or diarrhea could have liver damage and should see a physician as soon as possible. Untreated liver problems resulting from improper acetaminophen use can require long-term intensive treatment, including surgery in some cases.
While allergic reactions are among the rarer side effects of acetaminophen, they can sometimes be life-threatening. Rashes or hives on the skin are often the first indication of such reactions. Sufferers are typically not aware they have an allergy to acetaminophen until they take a dose of it. In severe cases, acetaminophen can case swelling of the throat and restricted breathing. This is known as anaphylaxis, which requires immediate medical intervention to counteract.
As a non-narcotic analgesic, acetaminophen is effective at relieving pain without causing a loss of consciousness beyond normal drowsy feelings. Any type of analgesic drug has a maximum rate of effectiveness by dosage as determined in laboratory tests. A dose of acetaminophen higher than recommended will likely not be more effective at relieving pain. Excessive doses will actually cause more harm than good in the body. The vast majority of side effects of acetaminophen, or any analgesic, are preventable by following all the proper instructions for dosage.