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Trimediazine For Horses

Trimediazine For Horses
50g Sachet (Pack of 10)

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  • 50g Sachet (Pack of 10) £37.49


Trimediazine is a combination of trimethoprim and sulfadiazine which together produce a powerful anti-bacterial effect. The broad spectrum of activity and high safety levels of Trimediazine mean that it is used for a wide range of infections in horses. These include respiratory, alimentary and general soft tissue infections. Examples would be pneumonia; pleurisy, strangles, infected wounds and septicaemia.

Contra-indications, warnings, etc

Operator warning
Avoid direct contact with skin and eyes. If contact occurs, wash affected area with copious amounts of water. Seek medical advice if irritation persists.
Gloves should be worn whilst handling this product.
Wash hands after use.
Use during pregnancy or lactation
This product can be safely administered during pregnancy and lactation.
Drug absorption may be greater if food is withheld for a few hours prior to dosing.
Do not use in horses intended for human consumption.
Treated horses may never be slaughtered for human consumption.
The horse must have been declared as not intended for human consumption under national horse passport legislation.

Need help or advice? Contact us:

  • Landline: 01582 842096
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  • Sat: 9:00am - 1:00pm (Collections only)
  • Email: [email protected]

All prices include VAT where applicable.

Medication Datasheets

50g Sachet (Pack of 10)

Trimediazine™ Plain Oral Powder


Trimediazine Plain is a white broad spectrum antibacterial powder for mixing with animal feed . Each sachet contains Trimethoprim 5% w/w and Sulfadiazine 25% w/w.


Trimediazine Plain is indicated for use in the treatment of bacterial diseases in horses, including upper and lower respiratory tract infections, alimentary tract infections and infected wounds.

Dosage and administration

For oral administration in the feed, .Tto be given at a rate of 30mg combined active ingredients per kg bodyweight.

Mix with a small quantity of feed. Each 50 g sachet provides a daily dose for a 500 kg horse. The dose may be administered daily, or divided and administered at 12 hourly intervals, for 5 days.


It is recommended that other feed be withdrawn until medicated feed has been consumed.

Contra-indications, warnings, etc

Do not use in horses with severe liver parenchymal damage or kidney damage or known sulphonamide sensitivity, or horses with blood dyscrasias or cardiac arrhythmias. Do not exceed 7 days continuous treatment

The use of Trimediazine Plain in horses under 1 year old should be avoided.

In the rat and rabbit, trimethoprim/sulfadiazine combinations did not produce any foetal abnormalities at doses of up to 600mg/kg, although minor effects on skeletal development were seen below this level. As no studies have been conducted in horses, use on pregnant mares should be avoided.

When administered to lactating females, small amounts of trimethoprim and sulfadiazine are present in the maternal milk. Since no studies have been reported on the effects of Trimediazine Plain on the development of new born foals, it would be prudent not to feed very young foals with milk obtained from mares being treated.

As there is no specific antidote, in case of overdose, treatment should be symptomatic.

Withdrawal period

Meat: 6 months

In accordance with the Horse Passport legislation (Commission Decision 2000/68/EC as implemented in national legislation) a 6 month withdrawal period applies to the use of this product.

Pharmaceutical precautions

Do not store above 25°C. Store in a dry place away from animal feeding stuffs. Add to feed immediately before administration. Discard any remaining medicated feed.

Any unused veterinary medicinal product or waste materials derived from such veterinary medicinal products should be disposed of in accordance with local requirements.

Legal category

Packaging quantities

10×50 g sachets.

Further information

ATC vet code: QJ01EW10

Sulfadiazine is a bacteriostatic antibiotic belonging to the sulphonamide group which acts by interference with the synthesis of nucleic acids. Trimethoprim is a reductase inhibitor which also interferes with the synthesis of bacterial nucleic acids. Sulfadiazine and trimethoprim act on the same metabolic pathway, resulting in potentiation of antibacterial activity.

Marketing Authorisation Number

Vm 08007/4036.

Delivery Information

How quickly do you deliver?

Under almost all products on our website is an Estimated dispatch time, check this for a delivery prediction specific to the item you are looking to purchase. These badges are updated live based on the stock levels we have and also those of our suppliers - so are usually very accurate, but cannot be guaranteed. In more general terms, we aim to dispatch all orders within 1 working day of receiving payment (and a prescription if required). If we cannot do so within 3 working days we will contact you by email.

What do you charge for delivery?

For UK delivery, we charge the following:

Order Total Weight Delivery
£0-£28.99 Under 2kg £2.99
2kg+ £4.99
£29-£38.99 Under 2kg Free
2kg+ £4.99
£39+ Under 2kg Free
2kg+ Free

Prices quoted are for delivery to all parts of mainland UK except certain Scottish postcodes (where the price is higher for items sent by courier. Delivery of food abroad (including Channel Islands, N. Ireland and other islands around the UK) is charged at a higher price and free delivery is not available. Temperature controlled products, such as Insulin, are also not always subject to the standard and/or free delivery options.

For full information on our delivery charges, including prices on heavy deliveries to Scotland and abroad, see our delivery information page.

We can deliver most items to all around the world, but prices do vary. To find the exact cost of shipping your item, and to see all options available, follow these steps:

  1. Put the items you wish to order in your basket
  2. Proceed to checkout and enter your delivery address, including country
  3. Delivery information including price will automatically update to what is available to you

Delivery of aerosols

Due to restrictions aerosols can't be sent by Royal Mail. We appreciate your understanding.

Delivery of temperature controlled items

Some products, such as insulin and frozen food, need to be delivered in insulated packaging to prevent them from getting too warm (or too cold) during transit from us to you. Purchasing any of these items in your order will result in a £1.99 charge being added to the total to cover the high cost of the insulated packaging materials. You only pay the £1.99 once per order, regardless of how many temperature controlled items you purchase in that order.

How do I cancel or return an order?

Please call us as soon as possible if you need to amend or cancel an order on 01582 842096. If your order has been processed for dispatch we will be unable to cancel or amend the order. You will however be able to return your product for a full refund*.

To return an item, you must contact us by phone or email to arrange this BEFORE posting any product back to us. We will explain the process at this stage for you.

*For full details on returns, see our terms and conditions page.


Q & A

Below are some recent questions we've received regarding Trimediazine For Horses, including answers from our team.

25 August 2017 at 8:34pm


Lisa Vaughan-Smith

  • VioVet customer since 2014
  • From: , France

dose the 45g paste contain only one syringe and one dosage, thanks

  • Veterinary Advisor

Yes the syringes are sold singly though you can order as many as you need. Each syringe provides one dose for a 500 kg horse. Each division on the dial-a-dose plunger provides sufficient product to treat 50 kg of bodyweight.