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POM-V Prescription Required

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

Active ingredients: Sulfamethoxazole, Trimethoprim

Form

Liquid

Species

Chickens Pigs

Manufacturer

Eurovet Animal Health B.V.

VMD MA No.

16849/3007

What it's used for

Broilers: Treatment and metaphylaxis of respiratory infections caused by Escherichia coli susceptible to trimethoprim and sulfamethoxazole where the diseas...

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

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Prescription required

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Clinical information

Methoxasol 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.

Broilers: Treatment and metaphylaxis of respiratory infections caused by Escherichia coli
susceptible to trimethoprim and sulfamethoxazole where the disease has been diagnosed
in the flock.
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 if required. Do not use this veterinary medicinal product
undiluted or in higher concentrated stock solutions.
Pigs: 25 mg TMPS per kg bodyweight per day for 3-4 days, corresponding to 1 ml of the
veterinary medicinal product per 4,8 kg bodyweight per day. This corresponds to
approximately 1 litre of the veterinary medicinal product in 500 L drinking water.
Based on the recommended dose, daily water consumption, and the number and weight of
the pigs to be treated, the exact daily concentration of the veterinary medicinal product
should be calculated according to the following formula:
Mean body weight (kg) of pigs to be
treated
=Mean daily water consumption (l) per
pig x 4.8
xx ml veterinary
medicinal product per l
drinking water
Broilers: 33 mg TMPS per kg bodyweight per day for 3-4 days, corresponding to 1 ml of
the veterinary medicinal product per 3,64 kg bodyweight per day. This corresponds to
approximately 1 litre of the veterinary medicinal product in 750 L drinking water.
Based on the recommended dose, daily water consumption, and the number and weight of
the birds to be treated, the exact daily concentration of the veterinary medicinal product
should be calculated according to the following formula:
Mean body weight (kg) of broilers to
be treated
=Mean daily water consumption (l) per
bird x 3.64
xx ml veterinary
medicinal product per
l drinking water
One litre of the veterinary medicinal product weighs 1079 gram; therefore weight can also
be used to measure the veterinary medicinal product quantity to be added in drinking
water, according to the following formula:
Amount to be added in drinking water (g/L) = calculated ml/L x 1.079.
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
other water sources than the medicated water the dilution of which should be calculated to
ensure that animals always have sufficient water available. To ensure a correct dosage
body weight should be determined as accurately as possible to avoid underdosing. The
intake of medicated water depends on the clinical condition of the animals. In order to
obtain the correct dosage the concentration of the veterinary medicinal product may need
to be adjusted accordingly.
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 sulfonamides or trimethoprim or to any of the
excipients.
Pigs:
Rare
(1 to 10 animals / 10,000 animals
treated):
Hypersensitivity reaction.
Chickens:
Rare
(1 to 10 animals / 10,000 animals
treated):
Hypersensitivity reaction, decreased drinking
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 the package leaflet for
respective contact details.
Severely diseased animals can have a decreased appetite and water consumption. If
necessary the concentration of the veterinary medicinal product in the drinking water may
need to 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 intake of water, pigs should be treated parenterally.

Special precautions for safe use in the target species:
Due to the likely variability (time, geographical) in susceptibility of bacteria for potentiated
sulphonamides, occurrence of resistance of bacteria
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
culture and sensitivity of micro-organisms from diseased cases on farm or from recent
previous experience on the farm. 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. Official and local antimicrobial policies should be taken into account when the
veterinary medicinal product is used.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
This veterinary medicinal product contains sulfamethoxazole, which can cause allergic
reactions in some people.
People with known hypersensitivity (allergy) to sulphonamides or trimethoprim should
avoid contact with the veterinary medicinal product.
During preparation and administration of the medicated drinking water, skin contact with
the drug should be avoided. Personal protective equipment consisting of impermeable
gloves e.g. rubber or latex should be worn when handling the veterinary medicinal product.
Do not handle this veterinary medicinal product if you know you are allergic to trimethoprim
or sulphonamides.
Do not smoke, drink or eat when handling the veterinary medicinal product.
If you develop symptoms following exposure to the veterinary medicinal product such as
skin rash, you should seek medical advice and show the package leaflet or the label to the
physician. Swelling of the face, lips or eyes or difficulty with breathing are more serious
symptoms and require urgent medical attention.
This veterinary medicinal product can cause eye-irritation.
Personal protective equipment consisting of safety glasses should be worn when mixing
the veterinary medicinal product with drinking water. In the event of eye contact, rinse the
eye with copious amounts of clean water and if irritation occurs, seek medical advice.
In the event of accidental ingestion, seek medical advice. Wash hands and contaminated
skin immediately after handling the veterinary medicinal product.
Laboratory studies in rabbits and rats conducted 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:
Not applicable.
Do not combine with other veterinary medicinal products.
Do not freeze.
Meat and offal:
Pigs: 5 days
Broilers: 6 days
Eggs:
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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