LANORINAL
Clinical safety rating: caution
Comprehensive clinical and safety monograph for LANORINAL (LANORINAL).
LANORINAL is a combination product containing acetaminophen, which inhibits cyclooxygenase (COX) enzymes and modulates cannabinoid receptors via its metabolite AM404; and butalbital, a barbiturate that enhances GABA-A receptor activity, producing sedative and anxiolytic effects.
| Metabolism | Acetaminophen is primarily metabolized by glucuronidation (UGT1A1, UGT1A6, UGT1A9) and sulfation (SULT1A1, SULT1A3); a minor pathway via CYP2E1 produces the toxic metabolite NAPQI. Butalbital is metabolized primarily by hydroxylation via CYP2C19. |
| Excretion | Renal: 30-50% unchanged; fecal/biliary: 50-70% as metabolites. |
| Half-life | Terminal half-life: 12-18 hours; prolonged to 24-36 hours in hepatic impairment. |
| Protein binding | 99% bound, primarily to albumin. |
| Volume of Distribution | 0.15-0.25 L/kg, indicating limited extravascular distribution. |
| Bioavailability | Oral: 70-85%. |
| Onset of Action | Oral: 30-60 minutes; IV: 5-10 minutes. |
| Duration of Action | 6-8 hours for analgesia; up to 12 hours for anti-inflammatory effect. |
1-2 mg intravenously or intramuscularly every 2-4 hours as needed for pain.
| Dosage form | TABLET |
| Renal impairment | GFR 30-50 mL/min: administer 75% of normal dose. GFR 10-29 mL/min: administer 50% of normal dose. GFR <10 mL/min: use not recommended. |
| Liver impairment | Child-Pugh A: no adjustment. Child-Pugh B: reduce dose by 50%. Child-Pugh C: contraindicated. |
| Pediatric use | 0.02-0.05 mg/kg intravenously or intramuscularly every 4-6 hours as needed; maximum single dose 2 mg. |
| Geriatric use | Initiate at 0.5-1 mg intravenously or intramuscularly; titrate cautiously due to increased sensitivity and risk of respiratory depression. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for LANORINAL (LANORINAL).
| Breastfeeding | Digoxin is excreted into breast milk with a milk-to-plasma (M/P) ratio of 0.8–0.9. The relative infant dose is approximately 1–5% of the maternal weight-adjusted dose, generally considered compatible with breastfeeding. Monitor infant for bradycardia and signs of digoxin toxicity (vomiting, arrhythmias). |
| Teratogenic Risk | LANORINAL (digoxin) is FDA pregnancy category C. First trimester: No well-controlled studies; animal studies show fetal toxicity at high doses. Second and third trimesters: No increased risk of major malformations with therapeutic doses; monitor for fetal bradycardia and digoxin toxicity due to increased maternal clearance. Risk of preterm labor and low birth weight from underlying maternal condition (e.g., heart failure). |
■ FDA Black Box Warning
Acetaminophen has been associated with cases of acute liver failure, sometimes resulting in liver transplant and death. Hepatotoxicity is often associated with use of acetaminophen in doses exceeding 4000 mg per day and often involves more than one acetaminophen-containing product.
| Serious Effects |
Hypersensitivity to acetaminophen, butalbital, or any component; severe hepatic impairment; porphyria; history of addiction to barbiturates; concomitant use with other barbiturates or potent CNS depressants (relative).
| Precautions | Risk of hepatotoxicity with high doses or chronic use of acetaminophen; hypersensitivity reactions including anaphylaxis; risk of CNS depression and respiratory depression with butalbital; potential for abuse, dependence, and withdrawal; interactions with alcohol and other CNS depressants; use with caution in patients with hepatic or renal impairment. |
Loading safety data…
| Fetal Monitoring | Monitor maternal serum digoxin levels (therapeutic range 0.5–2.0 ng/mL) and renal function. Fetal assessment: ultrasound for growth restriction, fetal heart rate monitoring for bradycardia. Maternal ECG for arrhythmias and signs of toxicity. During labor, continuous fetal monitoring is recommended. |
| Fertility Effects | No known direct effects on fertility in animal or human studies. Underlying cardiac disease may impact pregnancy success; treatment of maternal condition may improve fertility outcomes. |