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Opioid analgesic combination/Discontinued

LORTAB

LORTAB

Clinical safety rating

caution

Comprehensive clinical and safety monograph for LORTAB (LORTAB).


Mechanism of Action

Hydrocodone is a mu-opioid receptor agonist; acetaminophen inhibits cyclooxygenase (COX) and modulates pain pathways centrally.

What the body does with it

MetabolismHydrocodone: CYP3A4, CYP2D6; acetaminophen: hepatic conjugation (glucuronidation, sulfation) and CYP450 (minor).
ExcretionRenal: ~90% (unchanged: ~5% hydrocodone, ~60% hydromorphone and other conjugates; codeine-like metabolites). Biliary/fecal: minor (<10%).
Half-lifeHydrocodone: 3.3-4.4 hours in adults; prolonged in hepatic/renal impairment (up to 6-8 hours). Clinical context: requires 4-6 hour dosing intervals; steady-state in ~24 hours.
Protein bindingHydrocodone: ~20-30% bound (primarily albumin).
Volume of DistributionHydrocodone: 3.3-4.7 L/kg; indicates extensive tissue distribution.
BioavailabilityOral: ~90% (first-pass metabolism reduces to ~50% due to extensive hepatic extraction; absolute bioavailability not well defined, but high oral absorption).
Onset of ActionOral: 10-20 minutes; peak effect at 30-60 minutes.
Duration of Action4-6 hours (analgesic); may be extended with hepatic/renal impairment or in elderly.
Molecular WeightHydrocodone: 299.36 Da; Acetaminophen: 151.16 Da

Classification & Brands

Dosing & administration

1-2 tablets (each containing 5 mg hydrocodone/325 mg acetaminophen) orally every 4-6 hours as needed for pain. Maximum acetaminophen 3000 mg/day.

Dosage formTABLET
Renal impairmentHydrocodone: eGFR 30-59 mL/min: administer 50-75% of usual dose; eGFR 15-29 mL/min: 50% of usual dose; eGFR <15 mL/min: avoid or use with caution. Acetaminophen: no specific GFR-based adjustment; avoid in severe renal impairment due to metabolite accumulation.
Liver impairmentHydrocodone: Child-Pugh Class A: no adjustment; Class B: reduce dose by 50% and monitor; Class C: avoid. Acetaminophen: reduce dose or avoid in significant liver disease; maximum 2000 mg/day in mild-moderate impairment.
Pediatric useNot recommended for children <18 years due to risk of respiratory depression and acetaminophen toxicity. In specific circumstances, weight-based dosing for hydrocodone 0.1-0.2 mg/kg/dose every 4-6 hours, max 10 mg/dose; acetaminophen 10-15 mg/kg/dose, max 60 mg/kg/day, not to exceed 3000 mg/day.
Geriatric useStart at the low end of dosing range (e.g., 1 tablet of 5 mg hydrocodone/325 mg acetaminophen every 6 hours). Monitor for respiratory depression, sedation, and constipation. Avoid acetaminophen >3000 mg/day due to hepatotoxicity risk.

Use during pregnancy

1st trimesterContraindicated due to risk of neural tube defects and congenital malformations from acetaminophen component (hepatotoxicity) and opioid dependence; limited data, but avoid use.
2nd trimesterNot recommended; risk of fetal dependence, withdrawal, and respiratory depression; avoid unless absolute necessity.
3rd trimesterContraindicated in late pregnancy (especially after 37 weeks) due to risk of neonatal opioid withdrawal syndrome (NOWS) and respiratory depression; avoid use.

Clinical note

Comprehensive clinical and safety monograph for LORTAB (LORTAB).

Placental transferBoth hydrocodone and acetaminophen cross the placenta. Hydrocodone is highly protein-bound but undergoes placental transfer, detected in fetal plasma at concentrations similar to maternal. Acetaminophen readily crosses.
BreastfeedingTrace amounts of hydrocodone and acetaminophen pass into breast milk. Hydrocodone can cause infant sedation and respiratory depression, especially in CYP2D6 ultra-rapid metabolizers. Acetaminophen is considered compatible in low doses. Use with caution, monitor infant for drowsiness, and consider alternative analgesia if possible.
Lactation RatingL4 - Possibly Hazardous
Teratogenic RiskFDA Category C in 1st and 2nd trimesters; increased risk of neural tube defects and congenital heart defects with codeine use; risk of respiratory depression and neonatal withdrawal syndrome in 3rd trimester with prolonged use.
Fetal MonitoringMonitor maternal respiratory rate, oxygen saturation, and sedation level; fetal heart rate monitoring; assess neonatal withdrawal signs (NAS) after delivery.
Fertility EffectsMay affect reproductive hormones, potentially impairing fertility in both males and females; codeine can disrupt ovulation and spermatogenesis.

Warnings & precautions

■ FDA Black Box Warning

Risk of addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion; neonatal opioid withdrawal syndrome; risk with CYP3A4 inhibitors or discontinuation; risk of medication errors.

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to hydrocodone, acetaminophen, or any componentSignificant respiratory depressionAcute or severe bronchial asthma in an unmonitored setting or without resuscitative equipmentKnown or suspected gastrointestinal obstruction, including paralytic ileusConcurrent use of monoamine oxidase inhibitors (MAOIs) or within 14 days of such therapy

Clinical Precautions

PrecautionsAddiction, abuse, misuse; respiratory depression; head injury; GI obstruction; hepatic toxicity; renal impairment; hypotension; adrenal insufficiency; seizures; serotonin syndrome; severe hypotension; risk with MAOIs; pregnancy; lactation.
Food/DietaryAvoid grapefruit and grapefruit juice as they may alter hydrocodone metabolism. Alcohol must be strictly avoided due to additive CNS depression and increased acetaminophen hepatotoxicity. No other significant food interactions.

Clinical Tips & Counseling

Clinical PearlsLortab (hydrocodone/acetaminophen) carries a boxed warning for respiratory depression, misuse/abuse, and neonatal opioid withdrawal syndrome. The acetaminophen component imposes a maximum dose of 4000 mg/day; caution with hepatic impairment. Use the lowest effective dose for the shortest duration. Consider naloxone co-prescribing for high-risk patients.
Patient AdviceTake exactly as prescribed; do not increase dose or frequency without consulting your doctor. · Do not crush, chew, or dissolve tablets; swallow whole. · Avoid alcohol; it increases risk of liver damage and respiratory depression. · Do not drive or operate machinery until you know how Lortab affects you. · Discontinue and seek medical help if you experience signs of allergic reaction (rash, difficulty breathing) or liver injury (yellowing skin/eyes, dark urine). · Store securely out of reach of others; dispose of unused medication via take-back programs.

LORTAB 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

ANEXSIAANEXSIA 5/325ANEXSIA 7.5/325ANEXSIA 7.5/650ATROPINE AND DEMEROL

External sources

DailyMed (NIH) PubMed OpenFDA