Acetaminophen; Propoxyphene Napsylate (Darvocet)

What is it?

Darvocet is an opioid analgesic used to treat mild to moderate pain.

FDA approved:

Before 1982

Brand Names and International Availability:

Darvocet-N (US); Distalgesic (South-Africa); Dologesic; Dologesic-32 (Hong-Kong); Dolostop (Benin, Burkina-Faso, Ethiopia, Gambia, Ghana, Guinea, Ivory-Coast, Kenya, Liberia, Malawi, Mali, Mauritania, Mauritius, Morocco, Niger, Nigeria, Senegal, Seychelles, Sierra-Leone, South-Africa, Sudan, Tanzania, Tunia, Uganda, Zambia, Zimbabwe, Syria, Jordan, Iraq, Bahrain); Propacet;


How does it work?

Propoxyphene is a centrally acting narcotic analgesic agent. It works by changing the way your body feels pain. 


The usual dosage is 100 mg propoxyphene napsylate and 650 mg acetaminophen every 4 hours as needed for pain

How should I take it?

Take exactly as ordered by your doctor with a full glass of water. If it upsets your stomach you may take it with food or milk.


Those who have had a prior allergic reaction to propoxyphene or acetaminophen should not take Darvocet. 

Darvocet should be used with caution in those with a history kidney or liver disease.
Safe use in pregnancy has not been established in regards to possible adverse effects on fetal development.

Propoxyphene is not recommended for use in children.

Should be used with caution in those who are who depressed or addiction-prone.

Drug Interactions:

The CNS-depressant effect of propoxyphene is additive with that of other CNS depressants, including alcohol. 

Because of the potent nature of this medicine, be sure to tell your doctor about any other medicines you are taking, including nonprescription medicines and vitamins.

Possible side effects:

These side effects are not considered serious but are certainly annoying for those experiencing them. The most frequently reported side effects include dizziness, sedation, nausea, vomiting constipation, abdominal pain, skin rashes, lightheadedness, headache, weakness, hallucinations, and minor visual disturbances.  If these side effects occur and concern you, please contact your doctor.

Signs of a possible allergic reaction are rash, swelling and difficulty breathing. These symptoms should be reported immediately. 

Precautions & Special Notes:

LIMIT YOUR INTAKE OF ALCOHOL WHILE TAKING THIS DRUG. Make sure your doctor knows if you are taking tranquilizers, sleep aids, antidepressants, antihistamines, or any other drugs that make you sleepy. Combining propoxyphene with alcohol or these drugs in excessive doses is dangerous.

Use care while driving a car or using machines until you see how the drug affects you because propoxyphene can make you sleepy. Do not take more of the drug than your doctor prescribed. Dependence has occurred when patients have taken propoxyphene for a long period of time at doses greater than recommended.

Take only as ordered. Propoxyphene, when taken in higher-than-recommended doses over long periods of time, may produce drug dependence characterized by psychic dependence and, less frequently, physical dependence and tolerance.

Acetaminophen and propoxyphene may also cause constipation. Drink plenty of water (six to eight full glasses a day) to lessen this side effect. Increasing the amount of fiber in your diet can also help to alleviate constipation.

Never take more acetaminophen and propoxyphene than is prescribed for you. If your pain is not being adequately treated, talk to your doctor. 

Watch the acetaminophen content of other over-the-counter and prescription products while taking this medication. Do not take more than a total of 4 grams (4000 mg) of acetaminophen per day. 

For more information:

RxList: Propoxyphene Napsylate and Acetaminophen

MedicineNet: Propoxyphene Napsylate and Acetaminophen

Mosby’s GenRx®, 11th ed. Copyright © 2001 Mosby, Inc.