Respiratory infections, enteritis, and urinary tract conditions in livestock often spread systemically—affecting feed utilisation, growth rate, and overall herd resilience. In such cases, timely antimicrobial intervention with a broad-spectrum combination becomes essential to halt progression and support recovery.
Sulfamethoxazole + Trimethoprim bolus offers synergistic antibacterial action by targeting sequential steps in folate synthesis, making it effective even against strains with reduced sensitivity to single agents. Available in various strengths (1000+200 mg and 2000+400 mg), it enables tailored dosing for cattle, buffaloes, sheep, and goats—based on weight, species, and clinical severity.
Effective treatment, however, depends not just on the antimicrobial range—but on a formulation that performs under variable field conditions:
- Controlled disintegration profile for consistent systemic uptake
- High bioavailability to maintain therapeutic plasma concentrations
- Stability-assured matrix tested for storage in diverse climates
This bolus supports integrated infection control—where speed, coverage, and pharmacokinetics align to reduce relapse and ensure timely return to health.
That’s why Therawin Formulations, a WHO-GMP and ISO-certified veterinary manufacturer, focuses on formulation integrity—developing sulfonamide-based bolus that aligns with veterinary protocols and field-level demands.
Looking for a Sulfamethoxazole + Trimethoprim bolus manufacturer in India? Partner with Therawin Formulations—a trusted provider for veterinary pharma PCD franchises and third-party pharma manufacturing, delivering combination antimicrobials built for clinical precision and on-ground performance.
Generic name
Sulphamethoxazole 1000 mg / 2000 mg + Trimethoprim 200 mg / 400 mg
Pack
10 x 4 Blister
Description
This veterinary bolus delivers a fixed-dose combination of Sulfamethoxazole and Trimethoprim, formulated to treat bacterial infections across multiple livestock species. The combination targets systemic and localised infections by interfering with bacterial folate metabolism at two distinct enzymatic points.
- Sulfamethoxazole is a long-acting sulfonamide that inhibits dihydropteroate synthase, blocking the first step in folic acid synthesis required for bacterial DNA replication.
- Trimethoprim, a diaminopyrimidine compound, inhibits dihydrofolate reductase — the next enzyme in the same pathway — further preventing the production of tetrahydrofolate.
By acting at two sequential stages in the folate synthesis pathway, this combination achieves:
- Synergistic bactericidal activity, especially effective against both Gram-positive and Gram-negative pathogens
- Reduced risk of resistance due to dual-enzyme targeting
- Broad coverage of respiratory, gastrointestinal, urinary, and soft tissue infections commonly found in farm animals
This dual-action bolus enhances treatment outcomes in veterinary practice, ensuring reliable bacterial clearance and faster clinical recovery in infected livestock.
Sulphamethoxazole + Trimethoprim bolus uses
This fixed-dose antimicrobial bolus offers rapid relief from bacterial infections in livestock. It is widely used when laboratory diagnosis is pending, but swift control is needed to prevent worsening conditions.
Which infections does it treat?
- For cattle and buffaloes: Respiratory infections (such as pneumonia, bronchitis), mastitis due to susceptible strains, and post-surgical wound infections. (Administer orally using a sturdy bolus gun. Make sure the animal’s head is held firmly to avoid partial swallowing or chewing—doing so may interfere with the time-release mechanism.)
- For goats and sheep: Urinary tract infections, bacterial diarrhea, and early-stage septicemia. (Use a small-ruminant balling gun. These animals may resist if the bolus is too large—use the 1000 mg Sulfamethoxazole + 200 mg Trimethoprim version. Never crush or break the bolus unless the vet advises.)
- In mixed infections or doubtful diagnosis: Used as a broad-spectrum first-line treatment when culture reports are imminent but the infection is progressing. (Use only under veterinary direction if animals are on concurrent treatment. Dosage may require alteration depending on severity and previous use of antibiotics.)
It is not recommended in sulfonamides sensitive species.
Maintain regular dosing for 3–5 days or as directed by your veterinarian. Early discontinuation or missed doses can cause incomplete cure and resistance development.
Sulphamethoxazole + Trimethoprim bolus side effects
This combined antibiotic bolus is usually administered for respiratory, gastrointestinal, and systemic disease infection in livestock. Used appropriately, it has steady results. But misuse or individual animal sensitivity causes side effects—some temporary and minor, some requiring instant veterinarian intervention.
Mild & temporary reactions
(Common and usually manageable without intervention)
- Loss of appetite – Some may have reduced feed interest during the course. Induce feeding using fresh, palatable feed or supplements to help in recovery.
- Loose stools or bloating – Gut flora disruption may occur, especially in ruminants. Use probiotics or fibre-based feed to help in digestive balance.
- Skin rash or irritation – Redness, itching, or bumps may be signs of mild allergy to sulfonamides. Monitor closely and discontinue use if symptoms persist.
Rare & serious reactions
(Require immediate veterinary care)
- Kidney stress – Sulphonamides can crystallise in the kidneys, particularly in dehydrated animals. Signs are reduced urination, dark-coloured urine, or weakness. Provide lots of drinking water and veterinary attention immediately.
- Fever or joint stiffness – Hypersensitivity reactions are seldom autoimmune-like. Stop medication and consult a vet if the symptoms get worse.
- Anaphylaxis – Acute swelling, difficulty breathing, or collapse could be a severe allergy. Immediate veterinary intervention is necessary.
Common mistakes to avoid:
- Do not use during late pregnancy or lactation – The drug may interfere with fetal development and is excreted into milk.
- Never use in animals with known sulfonamide sensitivity or renal dysfunction – These groups are at high risk for adverse reactions.
- Ensure adequate hydration – Always offer free access to clean water during treatment to minimise kidney stress.
- Observe proper withdrawal times – Typically 7 days for milk and 28 days for meat. Skipping this step can result in drug residues in animal products, risking regulatory penalties.
How to store Sulfamethoxazole + Trimethoprim bolus?
- Avoid exposure to heat or direct sunlight: Sulfamethoxazole and Trimethoprim are light sensitive. UV light causes degradation, especially in unsealed packets—reducing the bolus’s ability to exert therapeutic blood levels in infected animals.
- Store in original blister packaging until use: Premature removal of the bolus enhances the likelihood of oxidation and microbial contamination. Association is dose ratio dependent; air or moisture exposure may cause uneven degradation, reducing synergy between the two drugs.
- Stay clear of feed storages or dosing areas: The bolus is very hygroscopic. Storage close to water buckets or loose feed can cause absorption of moisture, rendering the tablet chalky or crumbly—preventing proper delivery on administration.
Sulfamethoxazole + Trimethoprim bolus manufacturer and supplier in India
In livestock care, combination antimicrobials such as Sulfamethoxazole + Trimethoprim are usually applied when initial treatments do not work. But for veterinary wholesalers, the greater concern is whether the product works consistently under varying conditions—without jeopardising antimicrobial abuse.
That’s where most generic products fail.
We at Therawin Formulations specialise in livestock-specific antibiotic combinations with consistent field results. Operating in veterinary pharma production for 35+ years, we have experienced firsthand the adverse effects of variance in sulfamethoxazole–trimethoprim ratios that result in delayed healing, increased dropout rates, and resistance accumulation—primarily in large animals subjected to heat stress, dehydration, or post-calving exhaustion.
We solve these problems by:
- Strict 5:1 ratio adherence – To ensure consistent bacteriostatic activity in systemic and gut infections
- Controlled bolus disintegration – Designed for ruminal conditions, providing timely release in buffaloes and cattle
- Veterinary-first strategy – No feed-grade compromises, just prescription-matched quality
- Batch-tested and foil-sealed – For long-distance distributors working in humid or rural areas
- Custom pack sizes – Enabling both franchise distributors and institutional veterinary supply chains
Whether you are sourcing for a veterinary pharma PCD franchise network, operating a third-party pharma manufacturing contract, or establishing a multi-state distribution channel, Therawin’s formulation provides stock confidence, reduced failure rates, and improved compliance with veterinary usage protocols.