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Acetaminophen Injection

(a set a mee' noe fen)

Brand Name(s): Ofirmev®

Other Name(s): APAP, N-acetyl-para-aminophenol, Paracetamol

WHY is this medicine prescribed?

Acetaminophen injection is used to relieve mild to moderate pain and to reduce fever. Acetaminophen injection is also used in combination with opioid (narcotic) medications to relieve moderate to severe pain. 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.

Are there OTHER USES for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

HOW should this medicine be used?

Acetaminophen injection comes as a solution (liquid) to be injected into a vein over 15 minutes. It is usually given every 4 to 6 hours as needed to relieve pain or reduce fever.

What SPECIAL PRECAUTIONS should I follow?

Before receiving acetaminophen injection,

  • tell your doctor and pharmacist if you are allergic to acetaminophen, any other medications, or any of the ingredients in acetaminophen injection. Ask your pharmacist or doctor for a list of ingredients.

  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, or herbal products you are taking or plan to take. Be sure to mention anticoagulants ('blood thinners') such as warfarin (Coumadin); disulfiram (Antabuse); and isoniazid (INH, Nydrazid, in Rifamate, in Rifater). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Be sure to tell your doctor if you are taking any other products that contain acetaminophen (Tylenol, found in may prescription and non prescription medications for fever, pain, and cold or flu symptoms) so that your doctor can be sure you do not receive too much acetaminophen.

  • tell your doctor if you have or have ever had liver disease. Your doctor will probably tell you not to use acetaminophen injection.

  • tell your doctor if you drink or have ever drunk large amounts of alcohol, if you have had severe vomiting or diarrhea or think you may be dehydrated, if you are not able to eat and drink enough to stay healthy, and if you have or have ever had kidney disease.

  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving acetaminophen injection, call your doctor.

  • ask your doctor or pharmacist about the safe use of alcoholic beverages while receiving acetaminophen injection.

What SPECIAL DIETARY instructions should I follow?

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

What SIDE EFFECTS can this medicine cause?

Acetaminophen injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea
  • vomiting
  • constipation
  • headache
  • agitation
  • difficulty falling asleep and staying asleep
  • pain in the place where the medication was injected

Some side effects can be serious. If you experience any of these 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 injection may cause other side effects. Call your doctor if you have any unusual problems while receiving 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 (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about STORAGE and DISPOSAL of this medication?

Acetaminophen injection will probably be stored in the medical facility where you receive it. Talk to your doctor if you have any questions about storing your medication.

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

If someone receives too much acetaminophen injection, get medical help immediately, even if the person does not have any symptoms. Symptoms of overdose may include the following:

  • nausea
  • vomiting
  • loss of appetite
  • sweating
  • extreme tiredness
  • lack of energy
  • unusual bleeding or bruising
  • pain in the upper right part of the stomach
  • yellowing of the skin or eyes
  • flu-like symptoms
  • dark-colored urine
  • coma (loss of consciousness)

What OTHER INFORMATION should I know?

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

Ask your pharmacist any questions you have about acetaminophen injection.

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.

Dear patient

I am excited to announce that I will be relocating my practice to Houston Methodist DeBakey Cardiology Associates. Starting November 4, 2024, my new address will be:

Houston Methodist DeBakey Cardiology Associates
6550 Fannin St.
Smith Tower, Suite 1901
Houston, TX 77030

Please note that my phone number and fax number will also change to the following:
24-Hour Telephone: 713-441-1100
Fax: 713-790-2643
Clinical Support Telephone (M-F, 8-5): 713-441-3515

I am excited about caring for you in my new office and hope you will make the transition with me. I will also continue to refill your medications as I have in the past. To assist, please provide your pharmacy with my new contact information.

Please consider checking your prescription refills to verify that you have enough medication on hand to last you until your next visit. Please note that your medical records will remain at my former office until you authorize their transfer. If you choose for me to continue providing your medical care, please complete and sign the enclosed “Authorization for Release of Medical Records” form and fax it to 713-790-2643. Once we receive your authorization, we will be happy to process the request for you.

Thank you for entrusting me with your medical care. My new team and I are dedicated to making this transition as seamless as possible. For help scheduling an appointment and transitioning your care, please call my new office number above.

I look forward to continuing your care at my new location.

Sincerely,
Gopi A. Shah, MD

Dear patient

Dr. Albert Raizner, Dr. Michael Raizner, and Dr. Mohamed El-Beheary are excited to announce that our practice, Interventional Cardiology Associates, will merge with Houston Cardiovascular Associates on November 1, 2024.

Our new offices are similarly located in Houston, near the Texas Medical Center and in Sugar Land. Our in-hospital care will continue at Houston Methodist Hospital in the Texas Medical Center and Houston Methodist Sugar Land Hospital. Importantly, our new offices expand our services with state-of-the-art equipment and amenities. Our core values will always be, as they began over 40 years ago when Dr. Albert Raizner founded ICA:

Integrity – Compassion – Accountability

Our new address and contact information are:

Your medical records are confidential and remain available at our new locations. We consider it a privilege to serve as your cardiologists and look forward to your continuing with us. However, should you desire to transfer to another physician, you may request a copy of your records by contacting us at our new addresses and phone numbers listed above.

We thank you for your trust and loyalty. As always, we will continue to be here to take care of you. Please do not hesitate to contact us if you have any questions or concerns.

Sincerely,

Dr. Albert Raizner,
Dr. Michael Raizner,
Dr. Mohamed El-Beheary