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Acetaminophen - Injection

Pronunciation: a-SEET-a-MIN-oh-fen

Common Brand Name(s): Ofirmev

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Warning

Taking too much acetaminophen may cause serious (possibly fatal) liver disease. Adults should not take more than 4000 milligrams (4 grams) of acetaminophen a day. People with liver problems and children should take less acetaminophen. Ask your doctor or pharmacist how much acetaminophen is safe to take.

Do not use with any other drug containing acetaminophen without asking your doctor or pharmacist first. Acetaminophen is in many nonprescription and prescription medications (such as pain/fever drugs or cough-and-cold products). Check the labels on all your medicines to see if they contain acetaminophen, and ask your pharmacist if you are unsure.

Get medical help right away if you take too much acetaminophen (overdose), even if you feel well. Overdose symptoms may include nausea, vomiting, loss of appetite, sweating, stomach/abdominal pain, extreme tiredness, yellowing eyes/skin, and dark urine.

Daily alcohol use, especially when combined with acetaminophen, may damage your liver. Avoid alcohol.

See also How to Use.

Uses

This drug is used to treat mild to moderate pain and to reduce fever. It is also used in combination with opioid pain medications to help relieve moderate to severe pain.

How To Use

See also Warning section.

Read the Patient Information Leaflet if available from your pharmacist before you start using acetaminophen and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

This medication is given by injection into a vein as directed by your doctor, usually every 4 to 6 hours as needed for pain relief or to reduce fever. Each dose is usually given over 15 minutes.

The dosage is based on your medical condition, age, weight, and response to treatment. For children 12 years of age and younger, and for adults and teenagers weighing less than 110 pounds (50 kilograms), the dosage is based on weight and the maximum daily dosage is less than 4000 milligrams of acetaminophen. Consult your doctor or pharmacist for more details.

If you are using this medication at home, learn all preparation and usage instructions from your health care professional for this drug and for the infusion pump. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid.

Pain medications work best if they are used as the first signs of pain occur. If you wait until the symptoms have worsened, the medication may not work as well.

Tell your doctor if your condition lasts or gets worse.

Side Effects

See also Warning section.

Pain at the injection site may occur. Other side effects are uncommon. If you have any unusual side effects, contact your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

See also Warning section.

Before using acetaminophen, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this product, tell your doctor or pharmacist your medical history, especially of:

  • kidney disease
  • liver disease
  • regular use/abuse of alcohol

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this form of acetaminophen passes into breast milk. However, acetaminophen taken by mouth passes into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

See also Warning section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug are:

  • ketoconazole
  • levoketoconazole

This medication may interfere with certain lab tests, possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: nausea, vomiting, loss of appetite, sweating, stomach/abdominal pain, extreme tiredness, yellowing eyes/skin, dark urine.

Notes

Lab and/or medical tests may be done while you are using this medication. Keep all medical and lab appointments. Consult your doctor for more details.

Missed Dose

Not applicable.

Storage

If you are using this medication at home, consult the product instructions and your pharmacist for storage details. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

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