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Acetaminophen

(a set a mee' noe fen)

Why is this medication prescribed?   Return to top

Acetaminophen is used to relieve mild to moderate pain from headaches, muscle aches, menstrual periods, colds, sore throats, toothaches, backaches, reactions to vaccinations (shots), and to reduce fever. Acetaminophen may also be used to relieve the pain of osteoarthritis (arthritis caused by the breakdown of the lining of the joints). Acetaminophen will relieve symptoms but will not treat the cause of symptoms or speed recovery. Acetaminophen is in a class of medications called analgesics (pain relievers) and antipyretics (fever reducers). It works by changing the way the body senses pain and by cooling the body.

How should this medicine be used?   Return to top

Acetaminophen comes as a tablet, chewable tablet, capsule, suspension or solution (liquid), drops (concentrated liquid), extended-release (long-acting) tablet, and orally disintegrating tablet (tablet that dissolves quickly in the mouth), to take by mouth with or without food. Acetaminophen also comes as a suppository to use rectally. Acetaminophen is available without a prescription, but your doctor may prescribe acetaminophen to treat certain conditions. Certain combination products containing acetaminophen and other medications are available by prescription only. Follow the directions on the package or prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take acetaminophen exactly as directed. Do not take more or less of it or take it more often than directed on the package label or prescribed by your doctor. Taking more than the recommended amount may cause damage to your liver.

Acetaminophen comes alone and in combination with other medications. Some of these combination products are available by prescription only and are used to treat moderate to severe pain, migraine headaches, and other conditions. Some of these combination products are available without a prescription and are used to treat cough, cold symptoms, and other conditions. If your doctor has prescribed a medication that contains acetaminophen, you should be careful not to take any nonprescription medications that also contain acetaminophen.

If you are selecting a product to treat cough or cold symptoms, ask your doctor or pharmacist for advice on which product is best for you. Check nonprescription product labels carefully and ask your doctor or pharmacist about the ingredients in prescription combination products before using 2 or more products at the same time. These products may contain the same active ingredient(s) and taking them together could cause you to receive an overdose. This is especially important if you will be giving cough and cold medications to a child.

Nonprescription cough and cold combination products, including products that contain acetaminophen can cause serious side effects or death in young children. Do not give these products to children younger than 4 years of age. If you give these products to children 4-11 years of age, use caution and follow the package directions carefully.

If you are giving acetaminophen or a combination product that contains acetaminophen to a child, read the package label carefully to make sure that it is the right product for a child of that age. Do not give acetaminophen products that are made for adults to children. Some products for adults and older children may contain too much acetaminophen for a younger child. Drops made for infants are more concentrated (much more medication in each drop) than liquids made for older children.

Before you give an acetaminophen product to a child, check the package label to find out how much medication the child should receive. If you know the child's weight, give the dose that matches that weight on the chart. If you don't know the child's weight, give the dose that matches the child's age. Ask the child's doctor if you don't know how much medication to give the child.

Shake the suspension and drops well before each use to mix the medication evenly. Do not use a household teaspoon to measure the dose of liquid medications. Use the measuring cup provided by the manufacturer to measure each dose of the solution or suspension, and use the dosing device provided to measure each dose of the drops. Use the dosing device to slowly release the drops directly into the child's mouth near the inner cheek. Do not mix the drops with baby formula.

Swallow the extended-release tablets whole; do not split, chew, crush, or dissolve them.

Place the orally disintegrating tablet ('Meltaways') in your mouth and allow to dissolve or chew it before swallowing.

To insert an acetaminophen suppository into the rectum, follow these steps:

• Wash your hands thoroughly with soap and water.
• If the suppository is soft, hold it under cool water or place it in the refrigerator for a few minutes to harden it before removing the wrapper.
• Remove the wrapper, if present.
• If you were told to use half of the suppository, cut it lengthwise with a clean, sharp blade.
• Put on a finger cot or disposable glove, if desired (available at a pharmacy).
• Lubricate the suppository tip with a water-soluble lubricant such as K-Y Jelly, not petroleum jelly (Vaseline). If you do not have this lubricant, moisten your rectal area with cool tap water.
• Lie on your side with your lower leg straightened out and your upper leg bent forward toward your stomach.
• Lift upper buttock to expose the rectal area.
• Insert the suppository, pointed end first, with your finger until it passes the muscular sphincter of the rectum, about 0.5 to 1 inch (1.25 to 2.5 centimeters) in infants and 1 inch (2.5 centimeters) in adults. If not inserted past this sphincter, the suppository may pop out.
• Hold buttocks together for a few seconds.
• Remain lying down for about 15 minutes to avoid having the suppository come out.
• Try to avoid having a bowel movement for about an hour so that the medication in the suppository can be absorbed into the body.
• Discard used materials and wash your hands thoroughly.

Stop taking acetaminophen and call your doctor if your symptoms get worse; you develop new or unexpected symptoms, including redness or swelling; your pain lasts for more than 10 days; or your fever gets worse or lasts more than 3 days. Stop giving acetaminophen to your child and call your child's doctor if your child develops new symptoms, including redness or swelling, or your child's pain lasts for longer than 5 days, or fever get worse or lasts longer than 3 days.

Do not give acetaminophen to a child who has a sore throat that is severe or does not go away, or that occurs along with fever, headache, rash, nausea, or vomiting. Call the child's doctor right away, because these symptoms may be signs of a more serious condition.

Other uses for this medicine   Return to top

Acetaminophen may also be used in combination with aspirin and caffeine to relieve the pain associated with migraine headache.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?   Return to top

Before taking acetaminophen,

• tell your doctor and pharmacist if you are allergic to acetaminophen, any other medications, or any of the ingredients in the product. Ask your pharmacist or check the label on the package for a list of ingredients.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention anticoagulants ('blood thinners') such as warfarin (Coumadin); isoniazid (INH); certain medications for seizures including carbamazepine (Tegretol), phenobarbital, and phenytoin (Dilantin); medications for pain, fever, coughs, and colds; and phenothiazines (medications for mental illness and nausea). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have any serious medical condition.
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking acetaminophen, call your doctor.
• if you drink three or more alcoholic beverages every day, ask your doctor if you should take acetaminophen. Ask your doctor or pharmacist about the safe use of alcoholic beverages while taking acetaminophen.
• if you have phenylketonuria (PKU, a inherited condition in which a special diet must be followed to prevent mental retardation), you should know that some brands of acetaminophen chewable tablets may be sweetened with aspartame, a source of phenylalanine.

What special dietary instructions should I follow?   Return to top

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?   Return to top

This medication is usually taken as needed. If your doctor has told you to take acetaminophen regularly, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?   Return to top

Acetaminophen may cause side effects.

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:

• rash
• hives
• itching
• swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
• hoarseness
• difficulty breathing or swallowing

Acetaminophen may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/MedWatch/index.html] or by phone [1-800-332-1088].

What storage conditions are needed for this medicine?   Return to top

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose   Return to top

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

If someone takes more than the recommended dose of acetaminophen, get medical help immediately, even if the person does not have any symptoms. Symptoms of overdose may include:

• nausea
• vomiting
• loss of appetite
• sweating
• extreme tiredness
• unusual bleeding or bruising
• pain in the upper right part of the stomach
• yellowing of the skin or eyes
• flu-like symptoms

What other information should I know?   Return to top

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking acetaminophen.

Ask your pharmacist any questions you have about acetaminophen.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names   Return to top

Brand names of combination products   Return to top

Last Revised - 12/01/2008

American Society of Health-System Pharmacists, Inc. Disclaimer

AHFS^® Consumer Medication Information. © Copyright, 2008. The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

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