Propoxyphene/acetaminophen (By mouth)


Acetaminophen (a-seet-a-MIN-oh-fen), Propoxyphene Napsylate (proe-POX-i-feen NAP-si-late)

This medicine was withdrawn from the US market in November 2010 because it may cause rare but serious side effects. Treats mild to moderate pain. This medicine contains a narcotic pain reliever. Products containing propoxyphene were withdrawn from the U.S. market starting November 19, 2010.

Brand Name(s)

Propoxacet-N 100, Propoxacet-N

There may be other brand names for this medicine.

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to propoxyphene or acetaminophen (Tylenol®). You should not use this medicine if you have serious breathing or lung problems, such as severe asthma or very slow breathing (also called respiratory depression). Do not use this medicine if you have a serious bowel problem called paralytic ileus (bowels don't move).

How to Use This Medicine


  • Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
  • This combination medicine contains acetaminophen (Tylenol(R)). Carefully check the labels of all other medicines you are using because they may also contain acetaminophen. It is not safe to use more than 4 grams (4,000 milligrams) of acetaminophen in one day (24 hours).
  • You may take this medicine with food to avoid stomach upset.
  • Drink plenty of fluids to help avoid constipation.

If a dose is missed:

  • If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Throw any unused medicine by mixing it with used coffee grounds or kitty litter and place it in a sealable bag, empty can, or container.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are using medicine to treat HIV or AIDS (such as amprenavir, fosamprenavir, nelfinavir, ritonavir, Agenerase®, Lexiva®, Norvir®, Telzir®, or Viracept®), medicine to treat an infection (such as clarithromycin, erythromycin, troleandomycin, Biaxin®, Ery-Tab®, or Tao®), medicine to treat a fungus infection (such as fluconazole, itraconazole, ketoconazole, Diflucan®, Nizoral®, or Sporanox®), medicine for depression (such as nefazodone, Serzone®) medicine for heart rhythm problems (such as amiodarone, Cordarone®), medicine to prevent nausea or vomiting (such as aprepitant, Emend®), blood pressure medicine (such as diltiazem, verapamil, Calan®, Cardizem®, Isoptin®, or Verelan®), or a blood thinner such as warfarin (Coumadin®).
  • You should not use this medicine if you have used an MAO inhibitor (MAOI) such as Eldepryl®, Marplan®, Nardil®, or Parnate® within the past 14 days.
  • Tell your doctor if you are also using buprenorphine (Buprenex®), butorphanol (Stadol®), nalbuphine (Nubain®), pentazocine (Talwin®), or a phenothiazine medicine such as prochlorperazine, promethazine, Compazine®, Mellaril®, Phenergan®, Thorazine®, or Trilafon®.
  • Tell your doctor if you are using lamotrigine (Lamictal®), probenecid (Benemid®), propranolol (Inderal®), zidovudine (Retrovir®), birth control pills (such as Nordette®, Norinyl®, Ortho-Novum®, Ovcon®, or Triphasil®), or a water pill (such as furosemide, torsemide, Demadex®, or Lasix®).
  • Do not drink alcohol while you are using this medicine.
  • Do not eat grapefruit or drink grapefruit juice while you are using this medicine.
  • Tell your doctor if you are using any medicines that make you sleepy. These include sleeping pills, cold and allergy medicine, narcotic pain relievers, and sedatives.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breastfeeding. Tell your doctor if you have ever had thoughts about hurting yourself or others, or if you have a history of emotional or mental problems. Make sure your doctor knows if you have kidney disease, liver disease, heart disease, low blood pressure, or pancreas problems.
  • Tell your doctor if you have a history of head injury, brain tumor, seizures, or drug or alcohol abuse. Make sure your doctor knows if you have any kind of breathing problem, such as chronic obstructive pulmonary disease (COPD), asthma, or hypoventilation (breathing too slowly).
  • Talk to your doctor first before you stop taking this medicine and changing to another pain medicine.
  • This medicine can cause changes in heart rhythms, such as conditions called PR, QRS, and QT prolongation. It may change the way your heart beats and cause fainting, dizziness, lightheadedness, or serious side effects in some patients. Contact your doctor right away if you have any symptoms of heart rhythm problems, such as fast, pounding, or irregular heartbeats.
  • Taking too much of this medicine can cause serious problems, including death. Symptoms of an overdose may include decreased awareness or responsiveness; severe sleepiness; loss of consciousness; seizures (convulsions); pale or blue lips, fingernails, or skin; difficult or troubled breathing; irregular, fast, slow, or shallow breathing; chest pain; nausea, vomiting, or diarrhea; dizziness, lightheadedness, or fainting; or fast, slow, or uneven heartbeats. Call your doctor and get emergency help right away if you take too much of this medicine or have any of these symptoms.
  • This medicine may be habit-forming. If you feel that the medicine is not working as well, do not use more than your prescribed dose. Call your doctor for instructions.
  • Do not stop using this medicine suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.
  • This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
  • Make sure any doctor or dentist who treats you knows that you are using this medicine. Acetaminophen may affect the results of certain laboratory tests.
  • This medicine may cause constipation. This is more common if you use it for a long time. Ask your doctor if you should also use a laxative to prevent and treat constipation.
  • Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
  • Changes in behavior.
  • Dark-colored urine or pale stools.
  • Decrease in how much or how often you urinate.
  • Extreme weakness, shallow breathing, irregular heartbeat, sweating, or cold or clammy skin.
  • Fast, slow, or uneven heartbeat.
  • Lightheadedness or fainting.
  • Nausea, vomiting, loss of appetite, or pain in the upper stomach.
  • Red or black stools.
  • Seeing, hearing, or feeling things that are not there.
  • Seizures.
  • Severe confusion.
  • Sudden and severe stomach pain and fever.
  • Unusual tiredness or weakness.
  • Unusual bleeding or bruising.
  • Yellow of your skin or the whites of your eyes.

If you notice these less serious side effects, talk with your doctor:

  • Blurred vision or eye swelling.
  • Feelings of extreme happiness or sadness
  • Headache.
  • Mild nausea, vomiting, constipation, diarrhea, or stomach pain.
  • Skin rash.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last Reviewed on 06/12/2013

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission ( URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2013 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.