Tiamulin
Tiamulin hydrogen fumarate
Also known as: Denagard · TiaGard · 81723-hfu · SQ-14055 · SQ-22947 · tiamulin fumarate
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
Swine
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Swine dysentery | 7.7 mg/kg PO daily in drinking water | PO | q24h | 5 days | 🌎 NA |
| Swine pneumonia | 23.1 mg/kg PO daily in drinking water | PO | q24h | 5 days | 🌎 NA |
| Medicated premix | See the label for the product | PO | Continuous | Varies | 🌎 NA |
- Swine dysentery: See package directions for dilution instructions.
- Swine pneumonia: See package directions for dilution instructions.
- Medicated premix: Used for increased weight gain or disease control.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Tiamulin is a semisynthetic diterpene pleuromutilin-class antibiotic primarily utilized in swine medicine. It is highly effective against Mycoplasma spp., spirochetes (such as Treponema/Brachyspira hyodysenteriae, the causative agent of swine dysentery), and various gram-positive cocci (including most Staphylococcus and Streptococcus species, excluding group D).
While its activity against most gram-negative organisms is poor, it does maintain efficacy against Haemophilus pleuropneumoniae and select strains of E. coli and Klebsiella.
Clinical Pearl: Tiamulin's unique diterpene structure makes cross-resistance with other antibiotic classes less common. However, because it shares a ribosomal binding site with macrolides and lincosamides, concurrent use should be avoided to prevent competitive antagonism.
Mechanism of action
Tiamulin acts by binding to the 50S ribosomal subunit at the peptidyl transferase center → blocks the correct positioning of tRNA → inhibits bacterial protein synthesis.
It is generally bacteriostatic, but can become bactericidal at very high concentrations against highly susceptible organisms.
Safety & warnings
Contraindications
- Concurrent access to feeds containing polyether ionophores (e.g., monensin, lasalocid, narasin, salinomycin)
- Swine weighing over 250 pounds
Adverse effects
- Skin redness/erythema (rare, primarily over the ham and underline)
Precautions
Fatal Interactions: Tiamulin must never be administered to animals having access to feeds containing polyether ionophores (e.g., monensin, lasalocid, narasin, or salinomycin) as severe adverse reactions may occur.
Weight Restrictions: Not approved for use in swine weighing over 250 pounds.
Withdrawal Times: Variable slaughter withdrawal times apply depending on the dosage and formulation used (ranges from 2 to 7 days).
Drug interactions
Severe adverse reactions and potential toxicity can occur if administered to animals with access to these feed additives.
Concomitant use could lead to decreased efficacy secondary to competition at the 50S ribosomal binding site.
Monitoring
- Clinical efficacy (resolution of respiratory or enteric signs)
- Feed and water intake
Pharmacokinetics
Absorption
Well absorbed orally by swine. Approximately 85% of a dose is absorbed and peak levels occur between 2-4 hours after a single oral dose.
Distribution
Apparently well distributed, with highest levels found in the lungs.
Metabolism
Extensively metabolized to over 20 metabolites, some having antibacterial activity.
Elimination
Approximately 30% of these metabolites are excreted in the urine with the remainder excreted in the feces.
Overdose
Oral overdoses in pigs may cause transient salivation, vomiting, and CNS depression (calming effect).
Management: Discontinue the drug immediately and treat symptomatically and supportively if necessary. Provide clean, unmedicated drinking water.
Available products
Formulations
- Medicated Premix
- Oral Solution (Liquid Concentrate)
- Soluble Powder
Veterinary
- Tiamulin Medicated Premix: 10 grams/1 lb in 35 lb bags (Denagard 10)
- Tiamulin Solution: 12.3% tiamulin hydrogen fumarate in an aqueous base (Denagard Liquid Concentrate, TiaGard)
- Tiamulin Soluble Powder: 45% in 2.28 oz packets (Denagard Liquid Concentrate, TiaGard)
- Chlortetracycline/tiamulin premix
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Protect from moisture; store in a dry place. In unopened packets, the powder is stable up to 5 years. Fresh solutions should be prepared daily when using clinically.
Client information
- Daily Preparation: Prepare fresh medicated drinking water daily to ensure the medication remains effective.
- Handling Safety: Avoid direct contact with skin or mucous membranes when handling the concentrate or powder, as irritation may occur. Wash hands thoroughly after use.
- Feed Warning: Ensure pigs do not have access to feeds containing ionophores (like monensin or salinomycin) while on this medication, as this combination can cause severe, potentially fatal reactions.
- Adverse Signs: If you notice unusual skin redness (especially on the belly or hams), stop the medication, provide clean water, and contact your veterinarian.
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.