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Registry Hub
Opioid Analgesic/Discontinued

NORCET

NORCET

Clinical safety rating

caution

Comprehensive clinical and safety monograph for NORCET (NORCET).


Mechanism of Action

Combination analgesic: hydrocodone acts as a μ-opioid receptor agonist; acetaminophen inhibits cyclooxygenase (COX) and modulates endocannabinoid system, exerting central analgesic and antipyretic effects.

What the body does with it

MetabolismHydrocodone: extensively metabolized via CYP3A4 and CYP2D6 to hydromorphone and norhydrocodone. Acetaminophen: primarily metabolized by conjugation (glucuronidation and sulfation); minor oxidation via CYP2E1, CYP1A2, and CYP3A4 to toxic N-acetyl-p-benzoquinone imine (NAPQI).
ExcretionRenal: ~60% unchanged; hepatic metabolism to inactive glucuronide conjugates; biliary/fecal: <5%
Half-life2-4 hours (terminal); prolonged in hepatic impairment (up to 8-10 hours) and elderly
Protein binding95% bound; primarily to albumin and alpha1-acid glycoprotein
Volume of Distribution2-3 L/kg; indicates extensive tissue distribution
BioavailabilityOral: 80-100% (extensive first-pass metabolism reduces to ~60% active drug); IM: 100%
Onset of ActionOral: 30-60 minutes; IV: 5-10 minutes; IM: 15-30 minutes
Duration of Action4-6 hours (analgesic); clinical effect may last up to 8 hours due to active metabolite (nortriptyline)
Molecular WeightMethotrexate: 454.44 Da; Paracetamol: 151.16 Da

Classification & Brands

Dosing & administration

1-2 tablets (containing paracetamol 325 mg and tramadol 37.5 mg) orally every 4-6 hours as needed for pain, maximum 8 tablets per day.

Dosage formTABLET
Renal impairmentFor CrCl 30-50 mL/min: extend interval to every 6-8 hours. For CrCl <30 mL/min: not recommended. Avoid in severe renal impairment (CrCl <15 mL/min).
Liver impairmentChild-Pugh A: no adjustment. Child-Pugh B: reduce dose to 1 tablet every 8-12 hours. Child-Pugh C: contraindicated.
Pediatric useNot recommended in children <12 years due to tramadol risk of respiratory depression. For adolescents 12-18 years: same adult dosing based on pain severity, with maximum 8 tablets/day.
Geriatric useStart at lowest dose (1 tablet every 6-8 hours), monitor renal function, avoid in patients with respiratory compromise. Maximum 6 tablets/day for those >75 years.

Use during pregnancy

1st trimesterAvoid due to risk of neural tube defects and congenital anomalies; associated with methotrexate (a component) which is teratogenic.
2nd trimesterAvoid due to risk of fetal toxicity; methotrexate can cause fetal growth restriction and developmental abnormalities.
3rd trimesterAvoid; methotrexate may cause neonatal bone marrow suppression and pulmonary toxicity.

Clinical note

Comprehensive clinical and safety monograph for NORCET (NORCET).

Placental transferMethotrexate crosses the placenta extensively, achieving fetal concentrations similar to maternal levels. Paracetamol also crosses the placenta.
BreastfeedingMethotrexate is excreted into breast milk in low concentrations; however, due to the potential for serious adverse reactions in nursing infants, including immunosuppression and bone marrow suppression, breastfeeding is not recommended. Paracetamol is considered safe in usual doses.
Lactation RatingL4 - Hazardous
Teratogenic RiskNORCET (norethindrone acetate and ethinyl estradiol) is contraindicated in pregnancy. First trimester: Use is associated with a slightly increased risk of cardiovascular and limb defects. Second and third trimesters: Use may cause feminization of male fetuses, urogenital sinus abnormalities in females, and cardiovascular or genital anomalies. Overall, absolute risk is low, but use is not recommended.
Fetal MonitoringIf inadvertently used during pregnancy, monitor fetal anatomy via ultrasound for potential anomalies. No specific monitoring mandated if discontinued upon pregnancy diagnosis. Routine prenatal care is sufficient.
Fertility EffectsNo permanent adverse effects on fertility. May transiently delay return to ovulation after discontinuation; normal fertility typically resumes within 1-3 cycles.

Warnings & precautions

■ FDA Black Box Warning

Addiction, abuse, and misuse: can lead to addiction and fatal overdose. Life-threatening respiratory depression: risk highest at initiation and with dose increases. Accidental ingestion of acetaminophen can cause fatal hepatotoxicity. Neonatal opioid withdrawal syndrome: prolonged use during pregnancy can result in withdrawal in newborns. Concomitant use with benzodiazepines or other CNS depressants may cause profound sedation, respiratory depression, coma, and death. CYP3A4 inhibitors or discontinuation of CYP3A4 inducers can cause fatal respiratory depression.

Side Effect Profile

Serious Effects

Absolute Contraindications

PregnancyBreastfeedingSevere hepatic impairmentSevere renal impairmentBlood dyscrasias (e.g., aplastic anemia, leukopenia, thrombocytopenia)AlcoholismKnown hypersensitivity to any componentConcurrent use of other hepatotoxic drugs

Clinical Precautions

PrecautionsRisk of respiratory depression, especially in elderly or debilitated; increased risk of serotonin syndrome with concomitant serotonergic drugs; adrenal insufficiency; severe hypotension; hepatotoxicity due to acetaminophen; risk of overdose with concurrent acetaminophen-containing products; opioid-induced hyperalgesia; seizures in patients with epilepsy; impaired driving or operating machinery; use in patients with head injury or increased intracranial pressure.
Food/DietaryAvoid alcohol; increases risk of hepatotoxicity. No specific food interactions reported.

Clinical Tips & Counseling

Clinical PearlsNORCET (propoxyphene/acetaminophen) carries a black box warning due to QT prolongation and risk of fatal arrhythmias. Avoid in patients with prolonged QT interval or those on other QT-prolonging drugs. Seizure threshold is lowered at high doses. Monitor for dependence and withdrawal. Acetaminophen hepatotoxicity risk increases with alcohol use or hepatic impairment.
Patient AdviceDo not exceed recommended dose; severe liver damage can occur with too much acetaminophen. · Avoid alcohol while taking this medication to prevent liver damage. · May cause drowsiness or dizziness; avoid driving or operating heavy machinery until you know how it affects you. · Risk of dependence with prolonged use; do not stop abruptly without medical advice. · Inform your doctor of all medications you are taking, especially other QT-prolonging drugs.

NORCET Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ABSTRALACEPHENACTIQALFENTAALFENTANIL

External sources

DailyMed (NIH) PubMed OpenFDA