Lincomycin
Lincomycin hydrochloride
Also known as: Lincocin · Lincomix · LincoMed · Linco-Ped · Lincono · Macrolin · Lincoject · U-10149 · NSC-70731 · Anbycin · Frademicina · Fredcina · Lincomicina · Lincomycine · Lincomycinum
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Skin and soft tissue infections | 15.4 mg/kg PO q8h or 22 mg/kg PO q12h | PO | q8h or q12h | Superficial pyoderma 21-42 days; deep, resistant pyoderma 56 days | 🌎 NA |
| Systemic infections | 22 mg/kg IM, SC, or IV (must be diluted and given as a slow drip infusion) q24h or 11 mg/kg IM or SC q12h | IM, SC, IV | q24h or q12h | 12 days or less | 🌎 NA |
| Bacteremia, sepsis | 11-22 mg/kg IV q8h | IV | q8h | 12 days or less | 🌎 NA |
| Pyoderma | 40-50 mg/kg/day PO divided into two or three doses per day | PO | Divided into two or three doses per day | — | 🌎 NA |
| Superficial pyodermas | 20 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| Pyoderma | 22 mg/kg PO twice daily | PO | Twice daily | — | 🌎 NA |
| Susceptible bacterial infections | 22 mg/kg | IM | q24h | — | 🌍 EU |
| Susceptible bacterial infections | 11 mg/kg | IM | q12h | — | 🌍 EU |
| Susceptible bacterial infections | 11-22 mg/kg | IV | q12-24h | — | 🌍 EU |
| Susceptible bacterial infections | 22 mg/kg | PO | q12h | — | 🌍 EU |
| Susceptible bacterial infections | 15 mg/kg | PO | q8h | — | 🌍 EU |
- Systemic infections: IV must be diluted and given as a slow drip infusion
- Pyoderma: Good for first time pyodermas
- Susceptible bacterial infections: Must be administered slowly
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Skin and soft tissue infections | 11 mg/kg IM q12h or 22 mg/kg IM q24h | IM | q12h or q24h | 12 days or less | 🌎 NA |
| Systemic infections | 15 mg/kg PO q8h or 22 mg/kg PO q12h | PO | q8h or q12h | 12 days or less | 🌎 NA |
| Susceptible bacterial infections | 22 mg/kg | IM | q24h | — | 🌍 EU |
| Susceptible bacterial infections | 11 mg/kg | IM | q12h | — | 🌍 EU |
| Susceptible bacterial infections | 11-22 mg/kg | IV | q12-24h | — | 🌍 EU |
| Susceptible bacterial infections | 22 mg/kg | PO | q12h | — | 🌍 EU |
| Susceptible bacterial infections | 15 mg/kg | PO | q8h | — | 🌍 EU |
- Susceptible bacterial infections: Must be administered slowly
Ferrets
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Susceptible infections | 10-15 mg/kg PO three times daily; 10 mg/kg IM twice daily | PO, IM | Three times daily (PO) or twice daily (IM) | — | 🌎 NA |
Swine
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Mycoplasmal (M. hyopneumoniae) pneumonia | Fed at 200 grams per ton of feed for 21 days or 11 mg/kg IM once daily | PO, IM | Continuous in feed or once daily IM | 21 days (feed) | 🌎 NA |
| Susceptible infections | 11 mg/kg IM once daily for 3-7 days; or added to drinking water at a rate of 250 mg/gallon (average of 8.36 mg/kg/day) | IM, PO | Once daily (IM) or continuous in water | 3-7 days (IM) | 🌎 NA |
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Lincomycin is a narrow-to-medium spectrum lincosamide antibiotic closely related to clindamycin. It is primarily utilized in veterinary medicine to treat infections caused by susceptible gram-positive aerobic cocci (such as Staphylococcus and Streptococcus spp.), various anaerobic bacteria, and Mycoplasma.
Key pharmacological characteristics include:
- Spectrum of Activity: Effective against many anaerobes, gram-positive aerobes, and Toxoplasma. It is generally inactive against gram-negative aerobes and Enterococcus faecalis.
- Clinical Utility: While FDA-approved for dogs, cats, and swine, its use in small animals has largely been supplanted by clindamycin, which boasts better oral bioavailability, higher intrinsic activity, and a lower toxicity profile.
- Toxicity Profile: It is strictly contraindicated in hindgut fermenters and ruminants (e.g., horses, rabbits, rodents) due to the risk of severe, often fatal, clostridial enterocolitis.
Clinical Pearl: Lincomycin is a time-dependent antibiotic. Maintaining drug concentrations above the Minimum Inhibitory Concentration (MIC) for the duration of the dosing interval is critical for clinical success.
Mechanism of action
Lincomycin exerts its antibacterial effects by binding to the 50S ribosomal subunit of susceptible bacteria.
Mechanism Pathway: Drug enters bacterial cell → Binds reversibly to the 50S ribosomal subunit → Blocks the transpeptidation and translocation steps → Inhibits bacterial protein synthesis.
Depending on the concentration of the drug at the infection site and the specific susceptibility of the targeted organism, lincomycin can be either bacteriostatic or bactericidal.
Note: Complete cross-resistance occurs between lincomycin and clindamycin, and partial cross-resistance occurs with macrolides like erythromycin due to overlapping ribosomal binding sites.
Safety & warnings
Contraindications
- Rabbits
- Hamsters
- Guinea pigs
- Horses
- Ruminants (cattle, sheep, goats)
- Patients with known hypersensitivity to lincosamides
- Patients with preexisting monilial (yeast) infections
- Neonatal animals (relative contraindication due to gut flora effects)
- Rapid intravenous administration
- Use with caution in patients with severe liver disease
Adverse effects
- Gastroenteritis (emesis, loose stools, bloody diarrhea in dogs)
- Pain and inflammation at IM injection sites
- Hypotension and cardiopulmonary arrest (if administered rapidly IV)
- Gastrointestinal disturbances in swine
- Diarrhea in nursing neonates (drug distributes into milk)
- Diarrhoea (potentially haemorrhagic)
- Colitis
- Hepatotoxicity (in patients with pre-existing liver disease)
- Cardiac depression (if given rapidly IV)
- Peripheral neuromuscular blockade (if given rapidly IV)
Precautions
Use with caution in patients with hepatic or renal dysfunction; consider reducing the dosage in severe cases as half-lives can be significantly prolonged.
Intravenous Administration: Must be diluted and given as a slow drip infusion to prevent severe hypotension and cardiopulmonary arrest.
Species Warnings: Never administer to horses, ruminants, or small herbivores (rabbits, guinea pigs, hamsters) as it can cause fatal dysbiosis and enterocolitis.
Drug interactions
Lincomycin may reduce systemic levels of cyclosporine.
In vitro antagonism occurs due to competing ribosomal binding sites; concomitant use should be avoided.
Reduces the absorption of oral lincomycin by up to 90%. If both are necessary, separate doses by at least 2 hours.
Lincomycin possesses intrinsic neuromuscular blocking activity and may enhance the effects of these agents; use cautiously.
Enhanced neuromuscular blockade action
Antagonistic antimicrobial action (competes for 50S ribosomal binding site)
Antagonistic antimicrobial action (competes for 50S ribosomal binding site)
Monitoring
- Clinical efficacy (resolution of infection)
- Adverse effects, particularly severe or bloody diarrhea
- Liver function tests (AST, ALT, Alk. Phosph.) may show slight, usually clinically insignificant, increases
- Fecal consistency (monitor for diarrhoea or haemorrhagic stool)
- Liver enzymes (in patients with pre-existing hepatic impairment)
Pharmacokinetics
Half-life
Absorption
Rapidly but incompletely absorbed from the gut (only about 30-40% of total dose). Food decreases both the extent and rate of absorption. Peak serum levels are attained 2-4 hours post-oral dosing, and about 30 minutes post-IM injection (IM peaks are double oral peaks).
Distribution
Distributes widely into most tissues including bone, synovial fluid, bile, pleural fluid, peritoneal fluid, skin, and heart muscle. CNS levels may reach 40% of serum levels if meninges are inflamed. Protein binding is 57-72%. Crosses the placenta and distributes into milk at concentrations equal to plasma.
Metabolism
Partially metabolized in the liver.
Elimination
Unchanged drug and metabolites are excreted in the urine, feces, and bile. Half-lives can be prolonged in patients with renal or hepatic dysfunction.
Overdose
There is limited information regarding acute overdoses. Lincomycin appears to have a wide margin of safety in dogs. Oral doses up to 300 mg/kg/day for up to one year, or parenteral doses of 60 mg/kg/day, did not result in apparent toxicity. If a massive overdose occurs, standard supportive care and gastrointestinal decontamination (if oral and recent) should be considered.
Available products
Formulations
- Oral tablets
- Oral solution (drops)
- Sterile injection
- Soluble powder/feed additive
- Injectable: 100 mg/ml solution
- Oral: powder for solution
Veterinary
- Lincomycin Oral Tablets: 100 mg, 200 mg, 500 mg (Lincocin)
- Lincomycin Oral Solution: 50 mg/mL in 20 mL dropper bottles (Lincocin Aquadrops)
- Lincomycin Sterile Injection: 100 mg/mL in 20 mL vials (Lincocin)
- Lincomycin Sterile Injection (Swine): 25 mg/mL, 100 mg/mL & 300 mg/mL in 100 mL vials (Lincocin Sterile Solution, Lincomix Injectable)
- Various combination feed/water additive products for swine and poultry
- Lincocin 100 mg/ml injection
- Lincoject 100 mg/ml injection
- Lincocin powder for oral solution
Human-labeled
- Lincomycin Injection: 300 mg/mL in 2 mL & 10 mL vials (Lincocin)
Regulatory status
POM-V classification
POM-V classification
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Capsules, tablets, and soluble powder should be stored at room temperature (15-30°C) in tight containers. Injectable products should be stored at room temperature; avoid freezing. Physically compatible for at least 24 hours in various IV fluids (D5W, 0.9% NaCl, Ringer's). Incompatible with ampicillin sodium, carbenicillin disodium, methicillin sodium, and phenytoin sodium.
Client information
- Administration: Give the medication exactly as prescribed. While food can decrease absorption, if your pet experiences mild stomach upset, giving it with a small treat or meal may help.
- Complete the Course: Do not stop the medication early even if your pet seems better, as this can lead to resistant infections.
- Adverse Effects: Contact your veterinarian immediately if you notice severe, protracted, or bloody diarrhea, vomiting, or loss of appetite.
- Nursing Pets: Inform your veterinarian if your pet is pregnant or nursing, as this drug passes into milk and may cause diarrhea in nursing offspring.
- Other Medications: Do not give over-the-counter anti-diarrheal medications containing kaolin within 2 hours of this drug, as it will prevent the antibiotic from being absorbed.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.