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POM-V Prescription Required

Trimsulfasol 20/100 mg/ml Solution for Use in Drinking Water for Pigs and Chickens

Active ingredients: Sulfamethoxazole, Trimethoprim

Form

Solution

Species

Chickens Pigs

Manufacturer

Dopharma Research B.V.

VMD MA No.

28365/3004

What it's used for

- Secondary bacterial infections caused by Pasteurella multocida, Actinobacillus pleuropneumoniae, Streptococcus spp. and . Broilers: Treatment and metaphy...

Full indications, dosage and side effects ↓
View official SPC (PDF)

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Prescription required

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Clinical information

Trimsulfasol 20/100 mg/ml Solution for Use in Drinking Water for Pigs and Chickens — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

- Secondary bacterial infections caused by Pasteurella multocida, Actinobacillus
pleuropneumoniae, Streptococcus spp. and .
Broilers:
Treatment and metaphylaxis of:
- Colibacillosis caused by Escherichia coli.
AN: 00413/2023Page 2 of 7
- Coryza caused by Avibacterium paragallinarum.
The presence of the disease in the group/flock must be established before the veterinary
medicinal product is used.
The veterinary medicinal product can be added directly to the drinking water to prepare a
therapeutic solution at the calculated concentration, but can also be used in a
concentrated stock solution by adding 200 ml of the veterinary medicinal product per litre
of water and diluting this further.
Fattening pigs:
5 mg trimethoprim and 25 mg sulfamethoxazole per kg body weight per day, for 4-7
consecutive days. This corresponds to 1 ml of the veterinary medicinal product per 4.0 kg
body weight per day.
Broilers:
7.5 mg trimethoprim and 37.5 mg sulfamethoxazole per kg body weight per day, for 3
consecutive days. This corresponds to 1 ml of the veterinary medicinal product per 2.67 kg
body weight per day.
To ensure a correct dosage, body weight should be determined as accurately as possible.
The intake of medicated water depends on the clinical condition of the animals. In order to
obtain the correct dosage, the concentration of trimethoprim/sulfamethoxazole may need
to be adjusted accordingly.
Based on the recommended dose and the number and weight of animals to be treated, the
exact daily concentration of the veterinary medicinal product should be calculated
according to the following formula:
…ml veterinary medicinal x average body weight (kg)
product/ kg body weight/day of animals to be treated
= … ml veterinary
average daily water intake (l/animal) medicinal product per
litre of drinking water
The daily amount is to be added to the drinking water such that all medication will be
consumed in 24 hours. Medicated drinking water and stock solutions should be freshly
prepared every 24 hours. During the treatment period animals should not have access to
water sources other than the medicated water. However, it should be ensured that animals
always have sufficient water available. After the end of the medication period, the water
supply system should be cleaned appropriately to avoid intake of sub-therapeutic amounts
of active substance.
AN: 00413/2023Page 5 of 7
Do not use in animals suffering from severe liver or kidney disease, oliguria or anuria.
Do not use in animals with impaired haematopoietic systems.
Do not use in cases of hypersensitivity to the active substances or to any of the excipients.
Chickens:
Rare
(1 to 10 animals / 10,000 animals
treated):
Hypersensitivity reactionUndetermined frequency
(cannot be estimated from the
available data):
Decreased drinking
Pigs:
Rare
(1 to 10 animals / 10,000 animals
treated):
Hypersensitivity reaction
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian, to
either the marketing authorisation holder or its local representative or the national
competent authority via the national reporting system. See also section ‘Contact details’ of
the package leaflet or the combined label and package leaflet.
Severely diseased animals can have a decreased appetite and water consumption. If
necessary, the concentration of the veterinary medicinal product in the drinking water
should be adjusted to make sure that the recommended dosage is being consumed.
However, if the concentration of the veterinary medicinal product is increased too much,
the intake of the medicated drinking water decreases for palatability reasons. Therefore,
water intake should be monitored regularly, especially in broilers.
In case of insufficient uptake of water, pigs should be treated parenterally.

Special precautions for safe use in the target species:
Due to the likely variability (time or geographically) in susceptibility of bacteria for
potentiated sulphonamides, occurrence of resistance of bacteria may differ from country to
country and even from farm to farm, and therefore bacteriological sampling and
susceptibility testing are recommended. Use of the veterinary medicinal product should be
based on identification and susceptibility testing of the target pathogen(s). If this is not
possible, therapy should be based on epidemiological information and knowledge of
susceptibility of the target pathogens at farm level, or at local regional level.
Use of the veterinary medicinal product deviating from the instructions given in the SPC
may increase the prevalence of bacteria resistant to sulfamethoxazole and trimethoprim
and may also decrease the effectiveness of combinations of trimethoprim with other
sulphonamides due to the potential for cross resistance. Use of the veterinary medicinal
product should be in accordance with official, national and regional antimicrobial policies.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
Sulphonamides may cause hypersensitivity (allergy) following injection, inhalation,
ingestion or skin contact. Hypersensitivity to sulphonamides may lead to cross reactions
with other antibiotics. Allergic reactions to these substances may occasionally be serious.
People with known hypersensitivity (allergy) to sulphonamides or trimethoprim should
avoid contact with the veterinary medicinal product. If you develop symptoms following
exposure, such as a skin rash, you should seek medical advice and show the package
leaflet or the label to the physician.
This veterinary medicinal product may cause skin- and respiratory irritation as well as eye
damage. During preparation and administration of the medicated drinking water, skin and
eye contact with the drug should be avoided. Personal protective equipment consisting of
AN: 00413/2023Page 3 of 7
impermeable gloves e.g. rubber or latex and protective glasses should be worn when
handling the veterinary medicinal product.
Avoid inhalation. Wash hands and contaminated skin immediately after handling the
veterinary medicinal product.
In the event of eye contact, rinse the eye with large amounts of clean water and, if irritation
occurs, seek medical attention.
In case of accidental ingestion, seek medical advice immediately and show the package
leaflet or the label to the physician.
Laboratory studies in rabbits and rats with the excipient N-methyl pyrrolidone have shown
evidence of foetotoxic effects. The veterinary medicinal product should not be
administered by pregnant women and women suspected of being pregnant. Personal
protective equipment consisting of gloves should be worn when handling the veterinary
medicinal product by women of childbearing age.
Special precautions for the protection of the environment:
Manure from animals treated with this veterinary medicinal product may cause toxic effects
to plants after spreading onto land. This risk can be reduced by avoiding too frequent and
repeated use of the veterinary medicinal product.
Do not combine with other veterinary medicinal products.
Do not refrigerate or freeze.
Protect from frost.
Pigs: meat and offal: 8 days.
Chickens: meat and offal: 5 days.
Not for use in birds producing or intended to produce eggs for human consumption.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.

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