LINCOMYCIN HCL
Clinical safety rating: caution
Comprehensive clinical and safety monograph for LINCOMYCIN HCL (LINCOMYCIN HCL).
Lincomycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, inhibiting peptide bond formation and translocation.
| Metabolism | Primarily hepatic via unknown enzymes; small amount excreted unchanged in urine and bile. |
| Excretion | Renal (approximately 40% unchanged in urine) and biliary/fecal (approximately 50% as active drug and metabolites). |
| Half-life | 4-5 hours (prolonged in renal impairment, up to 10 hours in anuria; no significant change in hepatic disease). |
| Protein binding | 70-85% bound, primarily to albumin. |
| Volume of Distribution | 0.7-1.3 L/kg (widely distributed, including bone, but low CNS penetration). |
| Bioavailability | Oral: 20-30% (subject to high first-pass metabolism); Intramuscular: 100% (absolute bioavailability). |
| Onset of Action | Oral: 2-4 hours; Intramuscular: 30-60 minutes; Intravenous: immediate. |
| Duration of Action | Oral: 6-8 hours; Intramuscular: 8-12 hours; Intravenous: 6-8 hours (bacteriostatic effect persists longer). |
| Molecular Weight | 443.0 Da (as hydrochloride salt; base: 406.5 Da) |
600 mg IM every 12-24 hours or 600 mg IV every 8-12 hours, up to 8 g/day for severe infections.
| Dosage form | Injectable |
| Renal impairment | For GFR 10-50 mL/min: administer 25-50% of usual dose every 12 hours or full dose every 12-24 hours. For GFR <10 mL/min: administer 25% of usual dose every 24 hours or full dose every 24-48 hours. |
| Liver impairment | In severe hepatic impairment (Child-Pugh C): reduce dose by 50-75% and monitor serum levels. Avoid use in acute hepatic failure. |
| Pediatric use | Neonates: 10 mg/kg IM/IV every 12 hours. Infants and children: 10-20 mg/kg/day IM/IV divided every 12-24 hours; for severe infections, up to 40 mg/kg/day divided every 6-12 hours. |
| Geriatric use | No specific dose adjustment; use with caution due to age-related renal decline. Monitor renal function and consider lower end of dosing range. |
| 1st trimester | Lincomycin crosses the placenta. Animal studies have shown no teratogenic effects, but adequate human studies are lacking. Use only if clearly needed. |
| 2nd trimester | Same as T1. Limited data suggest no increased risk of major malformations. |
| 3rd trimester | Use with caution near term due to potential for adverse effects on fetal gut flora and theoretical risk of kernicterus (displaces bilirubin from albumin). |
Clinical note
Comprehensive clinical and safety monograph for LINCOMYCIN HCL (LINCOMYCIN HCL).
| Placental transfer | Lincomycin crosses the placenta. Fetal serum levels reach approximately 50% of maternal serum levels. No documented teratogenicity in humans. |
| Breastfeeding | Lincomycin is excreted into human milk in small amounts (0.5-2.4% of maternal dose). It may cause gastrointestinal disturbance or alteration of infant gut flora. Caution in breastfeeding, especially in infants with known sensitivity or diarrhea. Monitor infant for loose stools or thrush. |
■ FDA Black Box Warning
Clostridioides difficile-associated diarrhea (CDAD) can occur, ranging from mild diarrhea to fatal colitis; use with caution in patients with history of gastrointestinal disease.
| Serious Effects |
Hypersensitivity to lincomycin or clindamycinPre-existing monilial infections (e.g., oral thrush, vaginal yeast)
| Precautions | Risk of severe pseudomembranous colitis, Neuromuscular blockade may occur with high doses; use caution in patients with neuromuscular disorders, Monitor renal and hepatic function in prolonged therapy |
| Food/Dietary | Avoid alcohol during therapy and for at least 48 hours after last dose due to risk of disulfiram-like reaction. No specific food restrictions; however, high-fat meals may slightly delay absorption, but no dose adjustment needed. Take with a full glass of water; may be taken with or without food. |
Loading safety data…
| Lactation Rating | L2 (Probably Compatible - Limited Evidence) |
| Teratogenic Risk | Pregnancy Category C. Animal studies have shown adverse effects on fetal development, but no adequate human studies. Risk cannot be ruled out; use only if clearly needed. First trimester: potential for teratogenicity, avoid unless essential. Second and third trimesters: limited data, use only if benefit outweighs risk. |
| Fetal Monitoring | Monitor maternal liver function, renal function, and complete blood counts periodically. Observe for signs of pseudomembranous colitis. Monitor fetal growth and well-being via ultrasound if used long-term. |
| Fertility Effects | No specific human studies on fertility. In animal studies, no adverse effects on fertility observed at therapeutic doses. |
| Clinical Pearls | Lincomycin HCl is a lincosamide antibiotic with bacteriostatic activity against Gram-positive cocci (except enterococci) and anaerobes. It is reserved for serious infections when penicillins are contraindicated or ineffective. Monitor for Clostridioides difficile diarrhea; pseudomembranous colitis can occur even after discontinuation. Dose adjustment required in hepatic impairment; no adjustment in renal impairment due to minimal renal clearance. Avoid rapid IV bolus (risk of cardiopulmonary arrest); infuse over at least 1 hour. Neuromuscular blockade potential: use caution with myasthenia gravis or concurrent neuromuscular blocking agents. |
| Patient Advice | Take lincomycin exactly as prescribed, with a full glass of water. · Space doses evenly to maintain constant blood levels. · If you miss a dose, take it as soon as remembered unless near next dose; do not double. · Report severe diarrhea, abdominal cramps, or bloody stools immediately. · Avoid alcohol during treatment and for 48 hours after completion to reduce GI side effects. · Finish entire course even if feeling better to prevent resistance. · Notify your doctor if you experience skin rash, itching, or difficulty breathing. · This medication may cause dizziness; avoid driving until you know how it affects you. |