| PROPOXYPHENE HYDROCHLORIDE
Darvon 642 , Novopropoxyn
Classifications: narcotic (opiate) agonist, analgesic; Therapeutic: narcotic analgesic, agonist
Pregnancy Category: C (D for prolonged use or at term)
Controlled Substance: Schedule IV
Napsylate: 100 mg tablets
Hydrochloride: 65 mg capsules
Centrally acting opioid structurally related to methadone. Acts as a weak agonist at opiate receptors within the CNS. Analgesic
potency about ? 2/3 that of codeine.
Relief of mild to moderate pain.
To suppress narcotic withdrawal symptoms.
Hypersensitivity to drug; suicidal individuals; alcoholism; dependence on opiates; safety during pregnancy [category C (D
for prolonged use or at term)] or in children is not established.
Kidney or liver disease; cardiac disease; biliary tract disease; pulmonary insufficiency.
Route & Dosage
|Mild to Moderate Pain
Adult: PO 65 mg HCl or 100 mg napsylate q4h prn (max: 390 mg HCl/d, 600 mg napsylate/d)
Note: 100 mg napsylate = 65 mg HCl
- Empty capsules and mix contents with water or food if unable to swallow capsule whole.
- Be aware that absorption may be delayed by presence of food in stomach.
- Store at 15°30° C (59°86° F).
Adverse Effects (≥1%)CNS:
Dizziness, light-headedness, drowsiness,
sedation, unusual fatigue
or weakness, restlessness, tremor, euphoria, dysphoria, headache, paradoxic excitement, mental
confusion, toxic psychosis, coma,
Nausea, vomiting, abdominal pain, constipation
, liver dysfunction. Special Senses:
Minor visual disturbances, pinpoint pupils (dilate with advancing hypoxia
Skin eruptions (hypersensitivity). Metabolic: Hypoglycemia
(patients with impaired kidney function), acidosis, nephrogenic diabetes
insipidus. Respiratory: Respiratory depression, pulmonary
edema. CV: Circulatory collapse,
and other cns depressants
add to CNS depression
, also fatalities reported with alcohol
use; may increase hypoprothrombinemic effects of warfarin;
may increase carbamazepine toxicity
through decreased metabolism
stimulation, anxiety, tremors, confusion. Herbal: St. John's wort
may increase sedation.
Readily from upper part of small intestine. Onset:
1560 min. Peak:
23 h. Duration:
46 h. Distribution:
Crosses placenta; distributed into breast milk. Metabolism:
In liver. Elimination:
In urine. Half-Life:
612 h, 3036 h for metabolite
Assessment & Drug Effects
- Evaluate need for drug since abuse potential is high.
- Monitor CNS effects, respiratory status and therapeutic effectiveness.
- Overdose: Prompt action required; fatalities occur commonly within first hour following overdosage.
Patient & Family Education
- Do not drive or engage in potentially hazardous activities until response to drug is known.
- Do not exceed recommended dose; do not use alcohol and other CNS depressants with propoxyphene.
- Lie down if dizziness, light-headedness, drowsiness, nausea, or vomiting occur while ambulating.
- Be aware that tolerance and physical or psychic dependence of the morphine type can occur with excessive use.