An analgesic in the opioid category.
It treats mild pain and also has antitussive and local anaesthetic effects.
Has been taken off the market due to concerns of fatal overdoses and heart arrhythmias.
Its onset of analgesia is 20–30 minutes and peak effects are seen about 1.5–2.0 hours after oral administration.
Trade name Darvon
Pregnancy category AU: C
Routes of administration-oral, IV, rectal
Bioavailability 40%.
Protein binding 78%.
Metabolism is liver-mediated, CYP3A4-mediated N-demethylation, aromatic hydroxylation, and ester hydrolysis.
Elimination half-life 6–12 hours; 30–36 hours for active metabolite, nordextropropoxyphene.
Excretion in Urine.
Is excreted in breastmilk to a minor degree.
A weak opioid, known to cause dependency among recreational users.
Was found to be helpful in relieving the symptoms of restless legs syndrome.
Was commonly used to ease the withdrawal symptoms in people addicted to opioids.
Not intended for use in patients who are prone to suicide, anxiety, panic, or addiction.
Side effects:
Constipation, Itching, drowsiness, sore throat, i,paired alertness,confusion, serious or fatal heart rhythms, and nausea.
Acts as a mu-opioid receptor agonist, and is a potent, noncompetitive α3β4 neuronal nicotinic acetylcholine receptor antagonist, as well as a weak serotonin reuptake inhibitor.
An overdose of dextropropoxyphene may lead to sedation, respiratory depression, and mood- or thought-altering effects.
In the presence of amphetamine, propoxyphene overdose increases CNS stimulation and may cause fatal convulsive seizures.
Direct cardiac effects include decreased heart rate,decreased contractility, and decreased electrical conductivity.
Before the FDA-directed recall, dextropropoxyphene HCl was available in the United States as a prescription formulation with paracetamol (acetaminophen) in ratio from 30 mg / 600 mg to 100 mg / 650 mg (or 100 mg / 325 mg in the case of Balacet), respectively: Darvocet.
Darvon was a pure propoxyphene preparation that did not contain paracetamol.
Propoxyphene did not show up on standard opiate/opioid tests because it is not chemically related to opiates.