It is very important that your doctor check the progress of you or your child while you are using this medicine. This will allow your doctor to see if the medicine is working properly and to decide if you or your child should continue to take it.
If your symptoms do not improve within a few days or if they become worse, check with your doctor.
Stop using this medicine and check with your doctor or dentist right away:
- If you are taking this medicine to relieve pain, including arthritis pain, and the pain lasts for more than 10 days for adults or 5 days for children or if the pain gets worse, new symptoms occur, or the painful area is red or swollen. These could be signs of a serious condition that needs medical or dental treatment.
- If you are taking this medicine to bring down a fever, and the fever lasts for more than 3 days or returns, the fever gets worse, new symptoms occur, or redness or swelling is present. These could be signs of a serious condition that needs treatment.
- If you are taking this medicine for a sore throat, and the sore throat is very painful, lasts for more than 2 days, or occurs together with or is followed by fever, headache, skin rash, nausea, or vomiting.
Many combination medicines contain acetaminophen, including products with brand names such as Alka-Seltzer Plus®, Comtrex®, Drixoral®, Excedrin Migraine®, Midol®, Sinutab®, Sudafed®, Theraflu®, and Vanquish®. Adding these medicines to the medicine that you are already taking may cause you to get more than a safe amount of acetaminophen. Talk to your doctor before taking more than one medicine that contains acetaminophen.
Check with your doctor right away if you or your child have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be symptoms of a serious liver problem.
If you will be taking more than an occasional 1 or 2 doses of acetaminophen, do not drink alcoholic beverages. To do so may increase the chance of liver damage, especially if you drink large amounts of alcoholic beverages regularly, if you take more acetaminophen than is recommended on the package label, or if you take it regularly for a long time.
Taking certain other medicines together with acetaminophen may increase the chance of unwanted effects. The risk will depend on how much of each medicine you take every day, and on how long you take the medicines together. If your doctor or dentist directs you to take these medicines together on a regular basis, follow his or her directions carefully. However, do not take any of the following medicines together with acetaminophen for more than a few days unless your doctor has directed you to do so and is following your progress:
- Aspirin or other salicylates
- Diclofenac (e.g., Voltaren®)
- Diflunisal (e.g., Dolobid®)
- Etodolac (e.g., Lodine®)
- Fenoprofen (e.g., Nalfon®)
- Floctafenine (e.g., Idarac®)
- Flurbiprofen, oral (e.g., Ansaid®)
- Ibuprofen (e.g., Motrin®)
- Indomethacin (e.g., Indocin®)
- Ketoprofen (e.g., Orudis®)
- Ketorolac (e.g., Toradol®)
- Meclofenamate (e.g., Meclomen®)
- Mefenamic acid (e.g., Ponstel®)
- Nabumetone (e.g., Relafen®)
- Naproxen (e.g., Naprosyn®)
- Oxaprozin (e.g., Daypro®)
- Phenylbutazone (e.g., Butazolidin®)
- Piroxicam (e.g., Feldene®)
- Sulindac (e.g., Clinoril®)
- Tenoxicam (e.g., Apo-Tenoxicam®)
- Tiaprofenic acid (e.g., Surgam®)
- Tolmetin (e.g., Tolectin®).
Acetaminophen may interfere with the results of some medical tests. Before you have any medical tests, tell the person in charge if you have taken acetaminophen within the past 3 or 4 days. If possible, it is best to call the laboratory where the test will be done about 4 days ahead of time, to find out whether this medicine may be taken during the 3 or 4 days before the test.
For diabetic patients:
- Acetaminophen may cause false results with some blood glucose (sugar) tests. If you notice any change in your test results, or if you have any questions about this possible problem, check with your doctor. This is especially important if your diabetes is not well-controlled.
For patients taking one of the products that contain caffeine in addition to acetaminophen:
- Caffeine may interfere with the results of a test that uses adenosine (e.g., Adenocard®) or dipyridamole (e.g., Persantine®) to help find out how well your blood is flowing through certain blood vessels. Therefore, you should not have any caffeine for 8 to 12 hours before the test.
If you think that you or anyone else may have taken an overdose of acetaminophen, get emergency help at once, even if there are no signs of poisoning. Signs of severe poisoning may not appear for 2 to 4 days after the overdose is taken, but treatment to prevent liver damage or death must be started as soon as possible. Treatment started more than 24 hours after the overdose is taken may not be effective.