Recently the safety of anti-inflammatory medications such as acetaminophen has been reconsidered by the FDA. Acetaminophen is common in many over-the-counter drug due to its use to reduce pain, inflammation and fever. Large or prolonged consumption of acetaminophen can cause liver damage. Acetaminophen is still safe and effective if you follow these tips to control your dosage.
Uses
Acetaminophen belongs to a class of drugs called nonsteroidal anti-inflammatory drugs. NSAIDs inhibit the production of prostaglandin signals involved in pain and inflammation by the inhibition of the COX-2 enzyme. Acetaminophen is included in many pain relievers, fever reducers, flu treatment and other medications.
Liver Damage
The tolerable upper limits of acetaminophen are 1,000 mg in a single dose or 4,000 mg daily. Individuals who consume more than three alcoholic drinks a day should limit their intake to 2,000 mg per day. The FDA is currently recommending lowering the tolerable upper limit to 650 mg per dose and 2,600 mg per day.
Acetaminophen is metabolized in the liver into nontoxic products. However, an intermediate product from one metabolic pathway is toxic. Large doses of acetaminophen cause this toxic intermediate to build up, causing damage to the liver.
Risk Factors
High alcohol or drug intake as well as existing liver damage raises your risk of liver damage from acetaminophen. Any serious medical condition may compromise your ability to metabolize acetaminophen. Your doctor may lower your tolerable upper limit accordingly.
Know Which Drugs Contain Acetaminophen
Acetaminophen is added to many prescription and over-the-counter medications, and the amount may sneak up on you. For over-the-counter medications, check the "Active Ingredients" list under the "Drug Facts" label. Prescription medications will have acetaminophen or APAP printed on the label. If you are unsure, ask a doctor or pharmacist.
Avoid Unnecessary Acetaminophen
Acetaminophen is bundled into many over-the-counter cold and flu remedies. You can purchase the medications separately to treat cough or congestion without needing to consume acetaminophen. When taking acetaminophen every four to six hours, keep track with a notepad of when and how much you took to avoid taking more than you realize.
When to See a Doctor
Seek medical help immediately if you have overdosed on acetaminophen or are experiencing symptoms of liver damage, including dark urine; clay-colored stool; low fever with nausea; stomach pain; loss of appetite; and jaundice, a yellowing of the eyes or skin. Consult a doctor of pharmacist if you are unsure about your acetaminophen dosage or if you have been taking acetaminophen for 10 days with no improvement of symptoms.
References
- PubMed Health: Acetaminophen
- FDA: Acetaminophen and Liver Injury: Q & A for Consumers
- Drugs.com: Acetaminophen
- "Drug and Metabolic Disposition: The Biological Fate of Chemicals"; Involvement of Human Cytochrome P450 2D6 in the Bioactivation of Acetaminophen; H. Dong, et al.; 2000
- FDA: Acetaminophen Information
