POM-V Prescription Required

Hydrotrim 500 mg/g + 100 mg/g Powder for Use in Drinking Water/Milk for Cattle, Sheep, Pigs and Chickens

Active ingredients: Sulfadiazine Sodium, Trimethoprim

Form

Powder

Species

Cattle Chickens Pigs Sheep

Manufacturer

Huvepharma NV

VMD MA No.

30282/3003

What it's used for

The presence of the disease in the group must be established before the veterinary medicinal product is used. Pigs Treatment and metaphylaxis of respirator...

Full indications, dosage and side effects ↓

View official SPC (PDF)

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Clinical information

Hydrotrim 500 mg/g + 100 mg/g Powder for Use in Drinking Water/Milk for Cattle, Sheep, Pigs and Chickens — SPC Details

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

The presence of the disease in the group must be established before the veterinary
medicinal product is used.
Pigs
Treatment and metaphylaxis of respiratory infections caused by Actinobacillus
pleuropneumoniae or Pasteurella multocida
suis or Escherichia coli.
The presence of the disease in the group must be established before the veterinary
medicinal product is used.
Chickens
Treatment and metaphylaxis of colibacillosis caused by Escherichia coli.
The presence of the disease in the flock must be established before the veterinary
medicinal product is used.

Cattle (pre-ruminant calves) and sheep (pre-ruminant lambs):

12.5 mg of sulfadiazine and 2.5 mg of trimethoprim per kg body weight
(corresponding to 25 mg of the veterinary medicinal product per kg body weight),
every 12 hours for 4 to 7 consecutive days, to be dissolved in the milk replacer.
Pigs:

25 mg of sulfadiazine and 5 mg of trimethoprim per kg body weight per day
(corresponding to 50 mg of the veterinary medicinal product per kg body weight per
day), for 4 to 7 consecutive days, to be dissolved in drinking water.
Chickens:

25 mg of sulfadiazine and 5 mg of trimethoprim per kg body weight per day
(corresponding to 50 mg of the veterinary medicinal product per kg body weight per
day), for 4 to 7 consecutive days, to be dissolved in drinking water.
Guidance for preparing veterinary medicinal product solutions:
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 sulfadiazine and trimethoprim
should be adjusted accordingly.
The use of suitably calibrated measuring equipment is recommended.
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:
mg veterinary
medicinal
product/kg body
weight/day
X
average body
weight (kg) of
animals to be
treated
average daily water intake (l/animal)
=
mg veterinary medicinal
product per litre of
drinking water/milk
replacer
Prepare the solution with fresh tap water (or milk replacer for cattle (pre-ruminant
calves)) immediately before use. Milk replacer should be prepared prior to the
addition of the veterinary medicinal product. The solution should be vigorously stirred
for 5 minutes. Medicated milk replacer should be consumed immediately after
preparation. Water uptake should be monitored at frequent intervals during
medication. The medicated drinking water should be the sole source of drinking
water for the treatment duration. Any medicated drinking water which is not
consumed within 24 hours should be discarded. After the end of the medication
period, the water supply system should be cleaned appropriately to avoid intake of
sub-therapeutic amounts of the active substance.
The maximum solubility of the veterinary medicinal product is 1g/L. During
dissolution, the solution should be stirred for at least 2 minutes. Solutions should be
checked visually for complete dissolution.
For stock solutions and when using a proportioner, take care not to exceed the
maximum solubility. Adjust flow rate settings of the dosing pump according to
concentration of the stock solution and water intake of the animals to be treated.

Do not use in ruminating animals.
Do not use in animals suffering from severe liver or kidney disease, oliguria or anuria.
Do not use in cases of hypersensitivity to the active substance or to any of the
excipients.

Chickens:
Very rare (<1 animal / 10,000 animals
treated, including isolated reports):
Decreased drinkingUndetermined frequency (cannot be
estimated from the available data)
Hypersensitivity reactions
Cattle (pre-ruminant calves), sheep (pre-ruminant lambs) and pigs:
Undetermined frequency (cannot be
estimated from the available data)
Hypersensitivity reactions
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
should be adjusted to make sure that the recommended dosage is being consumed.
Pigs, cattle (pre-ruminant calves) and sheep (pre-ruminant lambs): the uptake of
medication by animals may be altered as a consequence of illness. In case of
insufficient water uptake, animals should be treated parenterally instead, using a
suitable injectable veterinary medicinal product prescribed by the veterinarian.

Special precautions for safe use in the target species:
Due to the likely variability (time, geographical) in susceptibility of bacteria for
potentiated sulfonamides, 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. It is particularly of importance for E. coli
infections where high percentages of resistance are observed (see section 4.2).
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
Summary of product characteristics (SPC) may increase the prevalence of bacteria
resistant to sulfadiazine and trimethoprim and may also decrease the effectiveness of
combinations of trimethoprim with other sulfonamides due to the potential for cross-
resistance.
Use of the veterinary medicinal product should be in accordance with official, national
and regional antimicrobial policies.
To avoid deterioration of the kidneys due to crystalluria during treatment, it should be
ensured that the animal receives sufficient amount of drinking water.
This antimicrobial combination should only be used where diagnostic testing has
indicated the need for simultaneous administration of each of the active substances.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
This veterinary medicinal product contains sulfadiazine, trimethoprim and
polysorbate 80, which can cause allergic reactions in some people. Hypersensitivity
to sulfonamides may lead to cross reactions with other antibiotics. Allergic reactions
to these substances may occasionally be serious.
People with known hypersensitivity (allergy) to sulfonamides, trimethoprim or
polysorbate should avoid contact with the veterinary medicinal product.
Avoid skin and eye contact during preparation and administration. Wear personal
protective equipment consisting of impervious (latex or nitrile) gloves (in compliance
with Directive 89/686/EEC and EN374 norm), protective masks, eye protection and
suitable protective clothing. In case of accidental contact with the eyes or skin,
wash the affected area with plenty of water, and if skin rash occurs, seek medical
advice immediately and show the package leaflet or the label to the physician.
This veterinary medicinal product may be harmful if ingested. In case of accidental
ingestion, seek medical advice immediately and show the package leaflet or the
label to the physician.
Wash hands after use.
Special precautions for the protection of the environment:
Not applicable.

Do not administer concomitantly with coccidiostats or veterinary medicinal products
containing sulfonamides.
Do not associate with PABA (para-aminobenzoic acid).
Sulfonamides potentiate anticoagulants action.

This veterinary medicinal product does not require any special storage conditions.

Cattle (pre-ruminant calves)
Meat and offal: 12 days.
Sheep (pre-ruminant lambs)
Meat and offal: 12 days.
Pigs
Meat and offal: 12 days.
Chickens
Meat and offal: 12 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.