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Regumate Equine for Horses

Regumate Equine for Horses
150ml Bottle
1 litre Bottle

  • 150ml Bottle £38.99
  • 1 litre Bottle £138.49

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£38.99 to £138.49


Regumate Equine is used to control oestrus ("heat") in mares. It is supplied as a liquid to be given directly into the mouth, or added to a small amount of food. It can be given daily to a mare early in her season and usually within 3 days it will stop that oestrus. Regumate can continue to be given once daily afterwards to prevent the return to oestrus. When daily dosing stops, 95% of mares will show signs of returning to oestrus within 5 days.

Regumate is usually used to prevent the hormone-dependant behavioural changes associated with oestrus, or to control the timing of ovulation so that the timing of mating and birth can be organised.

Please Note: A syringe is not included with these products. For a syringe to take the fluid out of the bottle please click here.

Qualitative and quantitative composition

Each ml contains:

Active substance:

Altrenogest 2.20 mg


Butylhydroxyanisole (E320) 0.07 mg

Butylhydroxytoluene (E321) 0.07 mg

Sorbic acid (E200) 1.50 mg

Benzyl alcohol 10.00 mg

For a full list of excipients, see section "Pharmaceutical Particulars".

Pharmaceutical form

Oral Solution. Clear, light yellow oily solution.

Clinical particulars

Target species

Horses (mares)

Indications for use

In mares with significant follicular activity during the transitional period between seasonal anoestrus and the breeding season (follicles of at least 20-25 mm present at the beginning of treatment):

•Suppression/prevention of oestrus (usually after 1 to 3 days of treatment) during the prolonged oestrus periods occurring during this period.

•Control of the time of initiation of oestrus (approximately 90% of mares show signs of oestrus within 5 days following the end of treatment) and synchronization of ovulation (60% of mares ovulate between days 11 and 14 following the end of treatment).


Do not use in mares where uterine infection has been diagnosed.

Do not use in males.

Special warnings for each target species

In order to ensure effective use of the product, the presence of follicular activity in mares must be confirmed during the transitional period.

Special precautions for use

The medicated feed should be offered to mares being treated as soon as the product has been added, and not stored. Part consumed feed must be safely destroyed and not given to any other animal.

Operator warnings

-Women who may be, or are pregnant, should not use the product. Women of childbearing age should avoid contact with the product.

-This product should not be handled by persons with known or suspected progesterone-dependent tumours or thrombo-embolic disorders.

-Direct contact with the skin should be avoided. Personal protective clothing (gloves and overalls) must be worn when handling the product. Porous gloves may let this product pass through. Transcutaneous absorption may be even higher when the area is covered by an occlusive material, such as latex or rubber gloves. Accidental spillage on the skin should be washed off immediately with soap and water.

-Wash hands after treatment and before meals.

-In case of incidental contact with eye, rinse thoroughly with water for 15 minutes. Get medical attention.

-Effects of overexposure: repeated accidental absorption could lead to disruption of the menstrual cycle, uterine or abdominal cramping, increased or decreased uterine bleeding, prolongation of pregnancy or headache.

Adverse reactions

Adverse reactions, such as uterine infection, are extremely rare.

Use during pregnancy, lactation or lay


Not applicable.

However, accidental administration is not detrimental as studies in mares have not produced any evidence of teratogenic, foetotoxic or maternotoxic effects.


Use during lactation is unlikely to have detrimental effects.


Griseofulvin may alter the effects of altrenogest if administered concomitantly with this product.

Amounts to be administered and administration route

For oral administration.

0.044 mg altrenogest per kg bodyweight per day, for 10 consecutive days.

Carefully withdraw the volume of product corresponding to the mare bodyweight (1 ml per 50 kg bodyweight) and administer this volume via oral route.

- 150, 300 and 1000 ml bottles: Wearing gloves remove the original cap and in its place screw on the luer lock cap. Keeping the bottle upright, screw the syringe onto the luer lock cap orifice, turn the bottle upside down, and carefully withdraw the solution from the bottle using the syringe.

Turn the bottle right way up before detaching the syringe. Securely replace the small cap on the luer lock cap.

- 250 ml bottles: Remove the white cap and the aluminium foil seal from the neck of the measuring compartment. Keeping the bottle upright, press the body of the bottle until the required volume of product is accumulated into the measuring compartment. Carefully pour the content of the measuring compartment on the mare feed.

The product should be added to the mare’s feed, at a single feeding per day, or directly administered into the mouth using a syringe.


No negative effects have been observed in horses following up to five times the recommended dose of altrenogest for 87 days and at the recommend dose for continuous periods up to 305 days.

Withdrawal periods

Meat and offal: 9 days.

Not authorised for use in lactating animals producing milk for human consumption.

Pharmacological particulars

Pharmacodynamic properties Pharmacotherapeutic group: Sex hormones and modulators of the genital system,

ATCvet code: QG03DX90.

Altrenogest is a synthetic trienic C21 steroidal progestagen, belonging to the 19-nor-testosterone series. It is an orally active progestagen. Altrenogest decrease blood concentrations of the endogenous gonadotrophins, LH and FSH. As a consequence, it induces the regression of all large follicles

(>20-25 mm) and therefore blocks oestrus or ovulation. During the second half of the treatment period with the product, when all large follicles have regressed, there is a peak in FSH concentration which initiates a new wave of follicular growth. End of treatment is followed by a steady rise in LH concentration, which sustains follicular growth and maturation. These endocrine effects ensure that most mares ovulate during the four day period between days 11 and 14 after the end of the treatment course.

Pharmacokinetic properties

Altrenogest is rapidly absorbed following oral administration and can be detected in blood as soon as 10 minutes after dosing. Maximum serum concentrations are observed 2.5 hours following administration. Altrenogest is extensively metabolised in the liver. The terminal half-life following oral administration is 10.7 hours ± 4.3 hours. Altrenogest is eliminated both via urine and faeces, in similar proportions.

Pharmaceutical particulars


Butylhydroxyanisole (E320), Butylhydroxytoluene (E321), Sorbic acid (E200), Benzyl alcohol, Triglyceride Medium chain.

Major incompatibilities

None known.

Shelf life

Shelf-life of the veterinary medicinal product as packaged for sale: 3 years.

Shelf-life after first opening the immediate packaging:

•150 ml bottle: 14 days.

•250 ml, 300 ml and 1000 ml bottles: 28 days.

Special precautions for storage

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

Immediate packaging

The product is packaged in brown opaque 150, 250, 300 and 1000 ml polyethylene bottles sealed by an aluminium protective cap and closed by a plastic screwed-on stopper.

The 150 ml, 300 ml and the 1000 ml bottles are provided with a luer lock cap which, when screwed on the bottle neck, allows the user to safely and accurately withdraw the product with a syringe that can directly adjust on the luer lock cap.

The 250 ml bottle is equipped with a 12.5 measuring compartment.

Not all pack sizes may be marketed.


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

Part consumed feed must be safely destroyed and not given to any other animals.

Marketing Authorisation Holder (if different from distributor)

Marketing authorisation number

Vm 01708/4503.

Date of the first authorisation or date of renewal

27 October 2009.

Date of revision of the text

November 2012.

Any other information


Legal category


GTIN (Global Trade Item No)

Need help or advice? Contact us:

  • Landline: 01582 842096
  • Mon - Fri: 8:30am - 5:00pm
  • Sat: 9:00am - 1:00pm (Collections only)
  • Email: [email protected]

All prices include VAT where applicable.

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. The majority of light weight orders (less than 1.5kg) can be delivered for a flat rate of £10. For an accurate estimate of the delivery charge, please put the items you require in your basket and use the "Estimate Delivery" system on the shopping basket page (you only need to enter your country and postal/zip code) for a quick quote. For deliveries to the USA you may need to go to the checkout page and enter your full address to get a quote (as some services need your state in order to quote too). For more information on international deliveries, please see our delivery information page.

Delivery of aerosols

Due to air freight restrictions aerosols cannot ever be sent abroad 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.

Reviews (3)

Q & A

Below are some recent questions we've received regarding Regumate Equine for Horses, including answers from our team.

27 February 2017 at 3:20pm

Can I break the prescription up to order the drugs as needed rather than all at once

Fiona Craig

  • VioVet customer since 2015
  • From: Kent, United Kingdom

My vet has given me a prescription for 2 litres of Regumate, to save me the cost of generating another script in three months. However I can't afford to buy 2 litres in one go, can I order 1 litre now and hold the prescription for you to send the second litre at the end of May? Many thanks

  • Veterinary Advisor

Yes that is perfectly fine. You can order one bottle now then the remaining bottle in May. Just be aware that the prescription will expire after 6 months of the issue date though and we will not be able to dispense any remaining regumate off the prescription once 6 months has passed. But you can order the medication at anytime within the 6 month window so May is fine. I hope this helps.

1 February 2015 at 11:45pm

Will this work on swine like matrix


Is this the same as matrix

  • Non-Executive Director

Regumate and Matrix contain the same active ingredients, but one is marketed for horses and one for pigs.