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Opioid Analgesic/Discontinued

LERITINE

LERITINE

Clinical safety rating

caution

Comprehensive clinical and safety monograph for LERITINE (LERITINE).


Mechanism of Action

LERITINE (anileridine) is a synthetic opioid analgesic that acts as a mu-opioid receptor agonist, modulating pain perception and emotional response to pain.

What the body does with it

MetabolismHepatic metabolism via N-dealkylation and glucuronidation; CYP450 enzymes (likely CYP3A4) involved.
ExcretionRenal (70-90% as unchanged drug and metabolites); biliary/fecal (10-30%)
Half-life2-3 hours (terminal half-life in adults; may be prolonged in hepatic impairment or elderly, dosing adjustments recommended)
Protein binding85-95% bound primarily to alpha-1-acid glycoprotein and albumin
Volume of Distribution3-5 L/kg (extensive tissue distribution; high affinity for CNS and adipose tissue)
BioavailabilityOral: 40-60% (first-pass metabolism); Intramuscular: 70-80%
Onset of ActionIntravenous: 1-2 minutes; Intramuscular: 10-15 minutes; Oral: 30-60 minutes
Duration of ActionAnalgesic effect: 3-4 hours (IV/IM); 4-6 hours (oral) due to sustained release formulation
Molecular Weight311.4

Classification & Brands

Dosing & administration

Adults: 25-50 mg orally every 6 hours as needed for pain; not to exceed 200 mg/day.

Dosage formTABLET
Renal impairmentGFR 30-60 mL/min: reduce dose by 25%; GFR 15-29 mL/min: reduce dose by 50% and administer every 8-12 hours; GFR <15 mL/min: avoid use.
Liver impairmentChild-Pugh Class A: no adjustment; Child-Pugh Class B: reduce dose by 50% and administer every 8-12 hours; Child-Pugh Class C: avoid use.
Pediatric useWeight-based: 0.5-1 mg/kg/dose orally every 6 hours as needed; maximum 4 mg/kg/day.
Geriatric useAge >65 years: start at lower end of dosing range (12.5-25 mg orally every 6 hours), monitor for CNS and respiratory depression.

Use during pregnancy

1st trimesterAnimal studies have shown teratogenic effects; no adequate human studies. Avoid in first trimester unless benefit outweighs risk.
2nd trimesterMay cause fetal respiratory depression and dependency if used near term. Use only if clearly needed.
3rd trimesterAvoid in third trimester due to risk of neonatal opioid withdrawal syndrome and respiratory depression.

Clinical note

Comprehensive clinical and safety monograph for LERITINE (LERITINE).

Placental transferCrosses placenta; detectable in fetal plasma. Potential for fetal accumulation.
BreastfeedingExcreted in breast milk; may cause infant sedation and respiratory depression. Use with caution; monitor infant for signs of toxicity.
Lactation RatingL3 - Moderately Safe
Teratogenic RiskPregnancy category D. First trimester: Increased risk of congenital malformations, particularly neural tube defects and cardiac anomalies; avoid if possible. Second and third trimesters: Risk of fetal dependence and withdrawal syndrome, decreased fetal breathing movements, and neonatal respiratory depression at delivery; prolonged use may cause neonatal opioid withdrawal syndrome.
Fetal MonitoringMaternal: Respiratory rate, sedation level, bowel function, signs of tolerance or dependence. Fetal/neonatal: Heart rate variability, growth scans if chronic use, assessment for neonatal opioid withdrawal syndrome after delivery.
Fertility EffectsMay alter gonadotropin secretion, potentially causing estrogen deficiency, anovulation, and impaired fertility. Reversible upon discontinuation.

Warnings & precautions

■ FDA Black Box Warning

Risk of respiratory depression, addiction, abuse, misuse, and neonatal opioid withdrawal syndrome with prolonged use during pregnancy.

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to leritineSevere respiratory depressionAcute or severe bronchial asthmaParalytic ileusMAO inhibitor use within 14 days

Clinical Precautions

PrecautionsRespiratory depression, CNS depression, hypotension, biliary tract spasm, seizure threshold reduction, serotonin syndrome risk with MAOIs, tolerance/dependence, withdrawal, impaired mental/physical abilities.
Food/DietaryNo specific food interactions are known; however, maintain a balanced diet and avoid grapefruit juice as it may affect metabolism.

Clinical Tips & Counseling

Clinical PearlsLERITINE (anileridine) is a potent opioid agonist with rapid onset; monitor for respiratory depression, especially in opioid-naïve patients. Avoid concurrent use with MAOIs. Use with caution in patients with hepatic impairment due to hepatic metabolism.
Patient AdviceAvoid alcohol and other CNS depressants while taking LERITINE. · Do not drive or operate heavy machinery until you know how LERITINE affects you. · Take exactly as prescribed; do not increase dose or frequency without consulting your doctor. · Store in a secure place away from children and pets. · Do not share this medication with others; it can cause addiction and death.

LERITINE 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