Proxyphene

Overview

Propoxyphene is considered a narcotic pain reliever and cough suppressant. It triggers the narcotic (opioid) receptors in the brain but it is weaker than hydroconone, oxycodone, codeine and morphine. The drug, more commonly known as Darvon and Darvocet is used to relieve mild to moderate pain.

Propoxyphene or Dextropropoxyphene was FDA approved in August 1957. This prescription drug was used for purposes other than those listed by the manufacturer. In addition to addressing pain reduction, it also causes respiratory depression and sedation. Propoxyphene enhances drugs that slow brain functions such as barbiturates, alcohol, benzodiazepine sedatives and skeletal muscle relaxants.

The United States-sponsored clinical trial indicated that use of propoxyphene, a controlled drug, increases the risk of developing serious heart rhythm abnormalities that could be fatal.1 A separate clinical study done in the UK and EU indicated that propoxyphene increases the risk of suicides, and fatal overdosing. In 2009, propoxyphene was banned in the UK and EU. In 2010, the United States followed suit, and recalled the drug.

Screening Cut-off and Detection Time

The two cut-off levels involved in drug testing are the initial drug testing and the confirmatory drug testing. If the initial drug test has a negative result, this means that there could be presence of drug but its amount is below the cut-off level. If this test proves positive, then a confirmatory test is needed for precise reading.

The initial cut-off level for propoxyphene is 300ng/ml, within a detection period of 6 hours to 2 days. The accepted confirmatory cut-off level for propoxyphene is 200ng/ml.

DEA Drug Class

The Drug Enforcement Administration (DEA) is the United States federal agency in charge of drug-related trade, production, smuggling, use and abuse. It is the regulatory and implementing body of the 1970 Controlled Substance Act (CSA).There are five categories and schedules of substances, chemicals and drugs based on their medical use, safety and potential for abuse, based on CSA.

Propoxyphene is a Schedule IV drug.3 According to the CSA, drugs under this category has a low potential for abuse compared to Schedule III drugs. Drugs under this schedule are used for medical treatment in the United States, though Propoxphene is now banned for medical use. Abuse of such drugs could lead to psychological or physical dependence.

Drug Type

Propoxyphene is an opioid or narcotic pain reliever. It is medically used for the treatment of mild to moderate pain. Taking this medication does not necessarily stop the pain but more on the reduction of pain, and increased tolerance to pain. This drug also induces drowsiness. Banned for medical purpose by the FDA in 2010, propoxyphene is found to causes arrhythmia.4

Forms and Routes of Administration

Propoxyphene is available in the forms of oral capsule, oral tablet, oral suspension and extended release tablet. The drug is available in two doses: 65 mg oral capsule of propoxyphene hydrochloride; and 100 mg oral tablet of propoxyphene napsylate. Dose is taken every four hours.
Doctor’s prescription is based on:

  • Patient’s condition being treated
  • Comorbidities that may exist
  • Other medications being taken by the patient
  • Response to propoxyphene
  • Patient’s gender, age, weight, and height

Interaction with other Drugs

Propoxyphene cannot be taken together with other sedatives, pain medications, muscle relaxers, tranquilizers and other medications that slow down breathing. The following drugs are contraindicated with propoxyphene.

  • Cordarone, Pacerone (amiodarone)
  • Emend (aprepitan)
  • Tracleer (bosentan)
  • Vaprisol (conivpatan)
  • Decadron, Hexadrol (dexamethasone)
  • Gleevee (imatinib)
  • St. John’s Wort
  • Isoniazid
  • Antibiotics such as erythrocin, clarithromycin, rifampin
  • Antifungal medications such as fluconazole, clotrimazole, ketoconazole
  • Antidepressant
  • Barbiturates
  • Blood pressure or heart medications such as felodipine, verapamil, etc
  • HIV/AIDS medications such as delavirdine, fosamprenavir, ritonavir
  • Seizure medications such as phenytoin (Dilantin), felbamate (Felbatol)5

Brand Names

  • Algafan
  • Antalvic
  • Deprancol
  • Depromic
  • Dolocap
  • Doloxen
  • Doloxene
  • Darvon
  • Darvon-N
  • Dolene
  • Darvocet
  • Erantin
  • Femadol
  • Harmar
  • Kesso-Gesic
  • Propacet
  • Prophene 65
  • Propxychel

Uses of Amphetamines

As this drug falls under the opioids group, Propoxyphene is a narcotic pain killer or analgesic and therefore medically used to relieve mild to medium pain. It is a weak opioid but is known to cause dependency among recreational users. This drug is not recommended with poor genotype of the liver.
Dextropropoxyphene has used to relieve restless legs syndrome. In its purest form, this drug has been used to alleviate or ease withdrawal symptoms of opioid addicts. The effect may not be that much as mental cravings are not totally eliminated. However, physical withdrawal symptoms are alleviated.

Street Names

  • Pinks
  • Footballs
  • Pink Footballs
  • Yellow Footballs
  • 65’s
  • Pain Killer
  • Dan’s
  • D’s
  • Dance

Effects and Symptoms

This drug has a slight sedating effect that it is never advised to take Propoxyphene with another sedative or antidepressant drug. In combination with alcohol, the effects of this drug can be dangerous and even fatal. Even food laced with alcohol cannot be taken with Propoxyphene.

Short-Term Effects

  • Feeling Dizzy
  • Feeling Drowsy
  • Nausea
  • Vomiting
  • Stomach Pain
  • Constipation
  • Headache
  • Muscle Pain
  • Blurred Vision
  • Mild Skin Rash

Long-Term Effects

  • Addiction
  • Fatal Overdoses
  • Death
  • Shallow Breathing
  • Light Headed
  • Fainting
  • Confusion
  • Hallucination
  • Change in Behavior
  • Suicidal Thoughts
  • Seizure
  • Convulsions
  • Swelling of: Face, Lips, Tongue, Throat
  • Abnormal Heart Rhythms
  • Slow Heartbeat
  • Toxicity to the Heart
  • Jaundice
  • Yellowing of the Skin
  • Yellowing of the Eyes

Tolerance, Dependence and Withdrawal

Opioids such as Propoxyphene are susceptible to abuse as one’s system can easily build tolerance to them. When a user’s body gets used to the usual dose of this drug, he needs to get a higher dose to control his pain. For recreational users, a higher dose is required to attain the sedative and euphoric effects of the drug. As one’s tolerance builds up, psychological dependence on the drug develops. Eventually, physical dependence to the drug develops.
If propoxyphene dependence arises, it is not wise to go cold turkey in managing the addiction. The right approach is to consult with a qualified doctor or drug abuse rehabilitation center for the correct withdrawal program. Some of the more obvious symptoms of propoxyphene withdrawal are:

  • Headaches
  • Muscle aches
  • Chills
  • Insomnia
  • Anxiety
  • Sweats
  • Fever

Depression and drug cravings are psychological symptoms of withdrawal.

Health Conditions that Make Propoxyphene Dangerous

People with a history of suicidal actions and thoughts must not use propoxyphene. It should not be taken with sedatives such as Xanax or Valium, or antidepressant, or with large quantity of alcohol. Propoxyphene is addictive and should be used only under a doctor’s prescription.
Patients prescribed with Propoxyphene must not have:

  • Liver or kidney disease
  • Asthma, sleep apnea, COPD, and other breathing disorders
  • No history of brain tumor or head injury
  • No history of alcohol or drug addiction
  • No history of mental illness

Pregnancy –Propoxyphene, based on FDA pregnancy category C, could harm the unborn baby. Taking the drug during pregnancy may cause breathing problems, even addiction in a newborn.
Breastfeeding – This drug passes into the breast milk and could therefore harm a nursing baby.6

History

Based on the provisions of the United States 1938 Food, Drug & Cosmetic Act (FD&C Act), Propoxyphene, invented by Eli Lilly & Co, was approved for the treatment of mild to moderate pain in 1957. The two most popular brands of this drug are Darvocet and Darvon, with the former mixed with acetaminophen. This drug is in the top 25 list of the most prescribed drug in United States before its withdrawal from the legitimate drug marketplace.

According to the FDA some 600 million prescription of this drug may have been written since 1957. In 2007 alone, over 20 million prescriptions were dispensed for propoxyphene-based products, never mind the serious, adverse-effects.2

The consumer group Public Citizen asked for the removal of all propoxyphene-based pain relievers from the market in 1978 because of its addictive properties, and ease of overdosing on the drug. The petition was denied. The second petition came in 2006 but it wasn’t until 2010 that the FDA withdrew the drug and its variants from the market. The drug has left millions of users with cardiac problems and negative side effects.