POM-VPS Prescription Required

Magniject 25% w/v Solution for Injection

Active ingredient: Magnesium Sulphate Heptahydrate

Form

Injection

Species

Cattle Sheep

Manufacturer

Norbrook Laboratories Limited

VMD MA No.

02000/4129

What it's used for

Indicated in the treatment of hypomagnesaemia in cattle and sheep

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 Magnesium Sulphate Heptahydr...

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.

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Prescription required

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

Clinical information

Magniject 25% w/v Solution for Injection — SPC Details

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

Indicated in the treatment of hypomagnesaemia in cattle and sheep

Administer by subcutaneous injection only, observing aseptic technique.
Cattle : Up to 400 ml
Sheep: Up to 75 ml
Warm to body temperature before administration, and gently massage the site
of injection. For subcutaneous injection only, observing aseptic precautions.
Divide the total dose volume to be administered between 2 or more sites.

Do not administer intravenously.

None

None

i. Special precautions for use in animals
None
ii. Special precautions to be taken by the person administering the
veterinary medicinal product to animals
Care should be taken to avoid accidental self-injection
Wash hands after use.

Revised: July 2010
ATCVet code amended

None known

This product does not contain an antimicrobial preservative. Do not store
above 25
o
C.
Any solution remaining in the vial following withdrawal of the required dose
should be discarded.

(equivalent to Magnesium Sulphate anhydrous 12.21% w/v)
Excipients:
For a full list of excipients, see section

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.