POM-V Prescription Required

Phenoxypen Water Soluble Powder, 325 mg/g Powder for Use in Drinking Water for Pigs and Chickens

Active ingredient: Phenoxymethylpenicillin Potassium

Form

Liquid

Species

Chickens Pigs

Manufacturer

Dopharma Research B.V.

VMD MA No.

28365/4000

What it's used for

Prevention of mortality at a group level from necrotic enteritis in chickens caused by Clostridium perfringens susceptible to phenoxymethylpenicillin.

Full indications, dosage and side effects ↓

View official SPC (PDF)

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Clinical information

Phenoxypen Water Soluble Powder, 325 mg/g Powder for Use in Drinking Water for Pigs and Chickens — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.

Prevention of mortality at a group level from necrotic enteritis in chickens caused by
Clostridium perfringens susceptible to phenoxymethylpenicillin.

corresponding with,46 – 68 mg of the product per kg of body weight per day,
for 5 days.
Method of administration: oral use, dissolve in drinking water and use within 12 hours.
The maximum solubility is 250 g of the product per litre of drinking water.
The following calculation should be made to determine the quantity in gram of the
product to be added in 1000 litres of water:
mg product/ kg body weight/day x mean body weight of individual animals (kg) x
number of animals

Revised: July 2020
AN: 01840/2019
total water consumption of the house (litres) at the previous day
= mg product/l = g product/1000 l water

In dispensing the weight of the product to be used, the use of calibrated weighing
equipment is recommended.
Taking into account that sick animals may drink less, it is recommended to start
therapy with the higher dose, to compensate for a possible lower intake of medicated
water.
To ensure correct dosage, the body weight of the animals should be determined as
accurately as possible to avoid underdosing.
No other source of drinking water should be available during the medication period.
In cases of altered drinking water consumption in poultry, the concentration should be
adjusted so that the recommended dosage is achieved.

Do not use in cases of hypersensitivity to the active substance.

Although no adverse reactions have been seen after the administration of the product,
penicillins may cause vomiting, diarrhoea and alter gut flora with selecting resistant
bacteria.

The administration of the product may lead to an increase in medicated water
consumption.

Special precautions for use in animals
Use of the product should be based on susceptibility testing of the bacteria isolated
from chickens that have already died on the farm.
The product should not be used to compensate for poor hygiene and management of
the chicken houses.

Revised: July 2020
AN: 01840/2019
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
Phenoxymethylpenicillin may cause hypersensitivity reactions after injection,
inhalation, oral ingestion, skin or eye contact. Hypersensitivity to
phenoxymethylpenicillin may lead to cross-sensitivity to other penicillins and
cephalosporins, and vice versa. Allergic reactions caused by these substances can
sometimes be serious.
In case of accidental ingestion or serious symptoms of hypersensitivity reactions such
as skin rash following exposure, swelling of the face, lips or eyes or difficulty with
breathing, seek medical advice immediately and show the package leaflet to the
physician.
People with known hypersensitivity to penicillins or cephalosporins should avoid
contact with the veterinary medicinal product. In case of development of
hypersensitivity symptoms following exposure to the product, all further contact with
the product (and other medicines containing other penicillins or cephalosporins) should
be avoided.
Handle this product with great care to avoid exposure, taking all recommended
precautions. Wear protective clothing, impervious gloves and either a disposable half
mask respirator conforming to European Standard EN149 or a non-disposable
respirator conforming to European Standard EN140 with a filter to EN 143 when
mixing and handling the product. Wash hands immediately after handling the product.

Do not combine with bacteriostatic antibiotics.

Store below 25 ºC.
Do not refrigerate or freeze.
Protect from frost.
Store in the original package.

Revised: July 2020
AN: 01840/2019

Meat and offal: 2 days.
Eggs: zero days.
5.

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.