POM-V Prescription Required

Coldostin, 4800000 IU/g, Powder for Use in Drinking Water/Milk

Active ingredient: Colistin Sulphate

Form

Powder

Species

Cattle Chickens Pigs Sheep Turkeys

Manufacturer

Dopharma Research B.V.

VMD MA No.

28365/4010

What it's used for

In the case of metaphylaxis, the presence of the disease in the group must be established before the veterinary medicinal product is used.

Full indications, dosage and side effects ↓

View official SPC (PDF)

The prescription itself has a price. See what practices near you charge for a consultation and the written prescription fee.

Paying less for Colistin Sulphate

1

Ask your vet for a written prescription

They must provide one on request. Under the CMA Order the fee is capped at £21 from 2027.
2

Fill it at a registered online retailer

The CMA found online pharmacies 50–60% cheaper than practice dispensing on common medicines — typically £200–£300 a year.

Your prescription rights → VMD register of retailers →

Prescription required

Your vet must provide a written prescription on request. You can then purchase from any licensed online retailer.

Clinical information

Coldostin, 4800000 IU/g, Powder for Use in Drinking Water/Milk — SPC Details

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

In the case of metaphylaxis, the presence of the disease in the group must be established
before the veterinary medicinal product is used.

per 48 kg body weight daily for 3-5 consecutive days.
Chickens and turkeys:
75 000 IU of colistin sulfate per kilogram body weight i.e. 1 g of veterinary medicinal product
per 64 kg body weight daily for 3-5 consecutive days.
Duration of treatment should be limited to the minimum time necessary for the treatment of
the disease.
To ensure a correct dosage, body weight should be determined as accurately as possible.
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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 per kg
body weight per day
X
mean body
weight (kg) of
animals to be
treated
mean daily water consumption (litre per animal)
=.... mg veterinary
medicinal product per
litre of drinking water
The uptake of medicated water depends on the physiological and clinical conditions of the
animals. In order to obtain the correct dosage, the concentration of colistin sulfate has to be
adjusted accordingly.
The use of suitably calibrated measuring equipment is recommended.
The veterinary medicinal product may be introduced via a water proportioner pump. Select
the treatment dosage. Set the proportioner at the desired delivery rate. To prepare the stock
solution, place the indicated quantity of veterinary medicinal product in a 10-litre container,
fill with water and stir until dissolved. The maximum recommended concentration is 250
grams of veterinary medicinal product per 10 litres of drinking water and 500 mg of veterinary
medicinal product per litre of milk(replacer).
The medicated water should be the only source of drinking water for the animals for the
entire duration of the treatment period.
Water uptake should be monitored at frequent intervals.
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.
Medicated drinking water should be freshly prepared every 24 hours.
The medicated milk (replacer) should be used within 4 hours.

Do not use in cases of hypersensitivity to colistin sulfate or to any of the excipients.
Do not use in cases of resistance to polymyxins.
Do not use in horses, particularly in foals, since colistin sulfate, due to a shift in the
gastrointestinal microflora balance could lead to the development of antimicrobial
associated colitis (Colitis X), typically associated with , which may be
fatal.

None known.
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 or label for
respective contact details.

As an adjunct to treatment, good management and hygiene practices should be introduced
in order to reduce the risk of infection and to control the potential build-up of resistance.
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There is cross-resistance between colistin sulfate and polymyxin B.
Colistin sulfate exerts concentration-dependent activity against Gram-negative bacteria.
Following oral administration high concentrations are achieved in the gastrointestinal tract,
i.e. the target site, due to the poor absorption of the substance. These factors indicate that
a longer duration of treatment than the one indicated in section 3.9, leading to
unnecessary exposure, is not recommended.

Special precautions for safe use in the target species:
Do not use colistin sulfate as a substitute for good management practices.
Colistin sulfate is a last resort drug in human medicine for treatment of infections caused
by certain multi-drugresistant bacteria. In order to minimise any potential risk associated
with widespread use of colistin sulfate, its use should be limited to treatment or treatment
and metaphylaxis of diseases, and should not be used for prophylaxis.
Whenever possible, colistin sufate should only be used based on susceptibility testing. An
antibiotic with a lower risk of antimicrobial resistance selection (lower AMEG category)
should be used for first line treatment where susceptibility testing suggests the likely
efficacy of this approach.
Use of the veterinary medicinal product deviating from the instructions given in the SPC
may lead to treatment failures and increase the prevalence of bacteria resistant to colistin
sufate.In the case of newborn animals and animals with severe gastrointestinal and renal
disorders, systemic exposure to colistin sulfate may be increased. Neuro- and nephrotoxic
alterations may occur.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
People with known hypersensitivity to polymyxines, such as colistin sulfate, should avoid
contact with the veterinary medicinal product.
If symptoms such as rash appear after exposure, seek medical advice immediately and
show the package leaflet or the label to the physician. Swelling of the face, lips or eyes or
respiratory difficulties are the most serious signs which require urgent medical attention.
The veterinary medicinal product may be irritating to the eyes, skin and mucous
membranes.
When handling the veterinary medicinal product direct contact of the veterinary medicinal
product with the skin, eyes and mucous membranes and inhalation of dust particles should
be avoided. Use the veterinary medicinal product in places with suitable ventilation.
The wearing of approved dust masks (either a disposable half-mask respirator conforming
to European Standard EN 149 or a non-disposable respirator to European Standard EN
140 with a filter to EN 143), impervious gloves, overalls and safety glasses are
recommended during the handling and mixing of this veterinary medicinal product.
Wash exposed skin after preparation. In case of accidental projection into the eyes, rinse
abundantly with water.
Wash hands after use.
Wash your clothes daily after using the veterinary medicinal product.
Do not smoke, eat or drink when handling the veterinary medicinal product.
Special precautions for the protection of the environment:
Not applicable.
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After oral administration of colistin sulfate interaction with anaesthetics and myorelaxants
may not be excluded in individual cases.
The combination with aminoglycosides and levamisole should be avoided.
The effects of colistin sulfate may be antagonized by binary cations (iron, calcium,
magnesium) and by unsaturated fatty acids and polyphosphates.

Keep the original container tightly closed, in order to protect from light.

Cattle (calves) and sheep (lambs):
Meat and offal: 1 day.
Pigs:
Meat and offal: 1 day.
Chickens and turkeys:
Meat and offal: 1 day.
Eggs: zero days.
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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.