Drug Database - Darvon

Generic Name: propoxyphene (proe-POX-ih-feen)

Brand Names: Darvon®, Darvon-N®

Classification: Narcotic Analgesics

Issue Date: 1995

Darvon is used for relieving mild to moderate pain. Darvon is a narcotic analgesic. It works in the brain to decrease pain.

Do not use Darvon if you are allergic to any ingredient in Darvon, if you have severe diarrhea caused by antibiotic use (pseudomembranous colitis) or poisoning, or if you are taking sodium oxybate (GHB). Contact your doctor or health care provider right away if any of these apply to you.

UPDATE: July 7, 2009 be sure to read the article FDA Takes Actions on Darvon & Darvocet That Contain Propoxyphene.

Use Darvon as directed by your doctor. Check the label on the medicine for exact dosing instructions.

• Darvon may be taken with or without food. If stomach upset occurs, take with food to reduce stomach irritation.


• Darvon comes with an additional patient leaflet. Read it carefully and reread it each time you get Darvon refilled.


• Do not take more than your prescribed dose or take Darvon for longer than prescribed by your health care provider.


• If you miss a dose of Darvon and you are taking it regularly, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Darvon.

Some medical conditions may interact with Darvon. Tell your health care provider if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding


• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement


• if you have allergies to medicines, foods, or other substances


• if you have prostate problems, liver problems (eg, hepatitis), or kidney problems


• if you have a history of drug abuse or dependence or depression or have ever seriously considered suicide


• if you have had a head injury, increased pressure in your brain, growths in your brain, or seizures


• if you have inflammatory bowel problems or ulcers, urinary problems, or you have had abdominal surgery


• if you have lung or breathing problems (eg, asthma), thyroid problems, heart problems, or certain blood problems (porphyria)

Some MEDICINES MAY INTERACT with Darvon. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Anticoagulants (eg, warfarin) because side effects, including an increased risk of bleeding, may be increased by Darvon


• Carbamazepine because the risk of severe side effects and toxicity, including nausea, vomiting, loss of coordination, and involuntary eye movements, may occur


• Antidepressant medicines (eg, amitriptyline, phenelzine), anticonvulsants (eg, phenobarbital, phenytoin), barbiturate anesthetics (eg, thiopental), cimetidine, HIV protease inhibitors (eg, ritonavir), and terfenadine because side effects may be increased by Darvon


• Naltrexone because the effectiveness of Darvon may be decreased


• Sodium oxybate (GHB) because side effects, including increased risk of sleep duration and drowsiness leading to unresponsiveness and coma, may be increased by Darvon

This may not be a complete list of all interactions that may occur. Ask your health care provider if Darvon may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center (http://www.aapcc.org), or emergency room immediately. Symptoms may include:

• anxiety
• confusion
• dilated pupils
• irregular heartbeat
• muscle pain
• severe drowsiness or dizziness
• slow or difficult breathing
• weakness

Darvon may cause drowsiness or dizziness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Darvon. Using Darvon alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.

Use of alcohol with Darvon may cause serious side effects. Limit your intake of alcohol while taking Darvon. If you drink alcohol every day, do not take Darvon without talking to your health care provider first. The combination of Darvon and alcohol may cause liver damage.

Make sure your health care provider knows if you are taking tranquilizers, sleep aids, antidepressant medicines, antihistamines, or any other medicines that may make you sleepy. The combination of these products with Darvon may lead to serious side effects, including death.

If you experience dizziness, drowsiness, nausea, or vomiting, it may help to lie down.

Before you have any medical or dental treatments, emergency care, or surgery, tell the doctor or dentist that you are using Darvon.

Darvon may be habit-forming. Do not take more than the dose prescribed by your doctor or take Darvon for a longer period of time than prescribed by your doctor.

Use Darvon with caution in the ELDERLY because they may be more sensitive to its effects.

Use Darvon with extreme caution in CHILDREN. Use of Darvon is not recommended in CHILDREN younger than 12 years of age. Safety and effectiveness in this age group have not been confirmed.

PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using Darvon during pregnancy. Darvon is excreted in breast milk. If you are or will be breast-feeding while you are using Darvon , check with your doctor or pharmacist to discuss the risks to your baby.

When used for long periods of time or at high doses, Darvon may not work as well and may require higher doses to obtain the same effect as when originally taken. This is known as TOLERANCE. Talk with your doctor if Darvon stops working well. Do not take more than prescribed.

Darvon can cause DEPENDENCE if taken in higher doses than recommended by your health care provider or over a long period of time. Take Darvon exactly as prescribed by your health care provider. If you suddenly stop taking Darvon, you may experience WITHDRAWAL symptoms including:

• anxiety
• diarrhea
• fever, runny nose, or sneezing
• goosebumps and abnormal skin sensations
• nausea
• pain
• rapid heartbeat
• rigid muscles
• seeing, hearing, or feeling things that are not there
• shivering or tremors
• sweating
• trouble sleeping
• vomiting

Side Effects

If you experience any of the following SERIOUS side effects, stop taking Darvon and seek emergency medical attention:

• An allergic reaction:
• difficulty breathing
• closing of the throat
• swelling of the lips, tongue, or face
• hives
• anxiety
• cold or clammy skin
• confusion
• excessive sweating
• hallucinations
• loss of appetite
• loss of consciousness
• mental or mood changes
• seizures
• severe drowsiness or dizziness
• severe or persistent stomach pain
• vision changes
• weakness
• yellowing of the skin or eyes

Other, less serious side effects may be more likely to occur. Continue to take Darvon and talk to your doctor if you experience:

• constipation
• dizziness
• drowsiness
• lightheadedness
• nausea
• vomiting

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

Some medicines may interact with Darvon. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Anticoagulants (eg, warfarin) because side effects, including an increased risk of bleeding, may be increased by Darvon


• Carbamazepine because the risk of severe side effects and toxicity, including nausea, vomiting, loss of coordination, and involuntary eye movements, may occur


• Antidepressant medicines such as:
• amitriptyline
• phenelzine
• Anticonvulsants such as:
• phenobarbital
• phenytoin
• Barbiturate anesthetics such as:
• thiopental
• cimetidine
• HIV protease inhibitors (eg, ritonavir), and terfenadine because side effects may be increased by Darvon


• Naltrexone because the effectiveness of Darvon may be decreased


• Sodium oxybate (GHB) because side effects, including increased risk of sleep duration and drowsiness leading to unresponsiveness and coma, may be increased by Darvon

This may not be a complete list of all interactions that may occur. Ask your health care provider if Darvon may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

Drugs other than those listed here may also interact with Darvon. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

The U.S. Food and Drug Administration is taking several actions to reduce the risk of overdose in patients using pain medications such as Darvon and Darvocet that contain propoxyphene. The actions were taken because of data linking propoxyphene and fatal overdoses.

The agency is requiring manufacturers of propoxyphene-containing products to strengthen the label, including the boxed warning, emphasizing the potential for overdose when using these products. These manufacturers will also be required to provide a medication guide to patients stressing the importance of using the drugs as directed.

In addition, the FDA is requiring a new safety study assessing unanswered questions about the effects of propoxyphene on the heart at higher than recommended doses. Findings from this study, as well as other data, could lead to additional regulatory action.

"Physicians need to be aware of the risk of overdose when prescribing these drugs. They should carefully review patient histories and make appropriate treatment decisions based on the warnings and directions stated within the drug's label," said Janet Woodcock, M.D, director of the FDA's Center for Drug Evaluation and Research. "Prescribers and patients should be aware of propoxyphene's potential risks when used at doses higher than those recommended. Therefore, the FDA is requiring manufacturers to provide more information to help physicians and patients decide whether propoxyphene is the appropriate pain therapy."

To further evaluate the safety of propoxyphene, the FDA plans to work with several groups including the Centers for Medicare & Medicaid Services and the Veterans Health Administration to study how often the elderly are prescribed propoxyphene instead of other pain relievers and the difference in the safety profiles of propoxyphene compared to other drugs.

Propoxyphene manufacturers are required to submit the requested safety labeling changes to the FDA within 30 days, or to provide a reason why they do not believe such changes are necessary. If they do not submit new language, or if the FDA disagrees with the language the companies propose, the Food, Drug, and Cosmetic Act provides strict timelines for discussions regarding the changes. At the end of these discussions, the FDA may issue an order directing the labeling changes as deemed appropriate to address the new safety information.

Also today, the FDA denied a citizen petition from the public interest group Public Citizen requesting a phased withdrawal of propoxyphene. The agency said in its response that despite the FDA's serious concerns about propoxyphene, the benefits of using the medication for pain relief at recommended doses outweighs the safety risks at this time. The FDA also noted that it plans to further evaluate the safety of propoxyphene and will take additional regulatory action if necessary. Details of this decision can be found at:

http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm170268.htm.

Propoxyphene has been on the market since 1957. It is a widely prescribed member of a group of drugs known as opioids and is used as a treatment for mild to moderate pain.

The most frequent side effects of propoxyphene include lightheadedness, dizziness, sedation, nausea, and vomiting.