POM-V Prescription Required

Subestin 25 microgram/ml Oral Solution for Horses

Active ingredient: Clenbuterol Hydrochloride

Form

Liquid

Species

Horses

Manufacturer

Floris Holding B.V.

VMD MA No.

56190/3003

What it's used for

To be used alone or as adjuvant therapy.

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 Clenbuterol Hydrochloride

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

Subestin 25 microgram/ml Oral Solution for Horses — SPC Details

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

To be used alone or as adjuvant therapy.

The veterinary medicinal product should be administered twice a day with
approximately 12 hours (minimum 8 hours) in between according to the following
dosage:
Administer 0.8 micrograms clenbuterol hydrochloride per kilogram body weight (i.e.
0.7 micrograms clenbuterol per kg bodyweight), corresponding to 4 ml oral solution /
125 kg body weight, twice daily.
The duration of the treatment is a maximum of ten consecutive days.
The veterinary medicinal product is administered orally, through or over food.
This veterinary medicinal product is intended for individual animal treatment.

Do not use in cases of known hypersensitivity to the active substance or any of the
excipients.
Do not use in horses with known cardiac disease.
For use during pregnancy or lactation see section 3.7.

Horses
Rare
(1 to 10 animals / 10,000 animals
treated):
Sweating*
Muscle tremor
Tachycardia
Hypotension**
Restlessness
Lethargy
*mainly neck region
**slight
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 for
respective contact details.

None.

Special precautions for safe use in the target species:
In cases accompanied by bacterial infection the administration of antimicrobial
agents is recommended.
In case of glaucoma the veterinary medicinal product must only be used after a
careful benefit-risk assessment by the attending veterinarian.
Special precautions should be taken in case of halothane anaesthesia, since the
heart function can show increased sensitivity to catecholamines.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
This veterinary medicinal product contains clenbuterol, a beta-agonist, which may
cause adverse effects such as increased heart rate.
Dermal exposure and accidental ingestion, including hand-to-mouth contact should be
avoided. When using this veterinary medicinal product do not eat, drink or smoke to
avoid accidental intake of the veterinary medicinal product.
To avoid accidental ingestion by or exposure to a child, do not leave the filled syringe
unattended and close the bottle immediately and properly after use.
In case of accidental ingestion, seek medical advice immediately and show the
package leaflet or the label to the physician. Wash hands after use.
This veterinary medicinal product may cause embryotoxicity. Pregnant women should
take care when handling the veterinary medicinal product. Wear gloves to avoid skin
contact.
This veterinary medicinal product may cause hypersensitivity reactions. People with
known hypersensitivity to any of the excipients (parabens, polyethylene glycol and/or
triethanolamine) should avoid exposure to the veterinary medicinal product. In case of
hypersensitivity reactions or if irritation persists, seek medical advice and show the
package leaflet or label to the physician.
This veterinary medicinal product may be irritating to the skin and/or eyes. Avoid skin
and/or eye contact. In case of accidental skin contact, wash skin thoroughly. In case
of accidental eye contact, flush thoroughly with clean water.

Effects including side effects may be enhanced with simultaneous use with
glucocorticoids, ß2-sympathomimetics, anticholinergics and methylxanthines.
The veterinary medicinal product should not be used concomitantly with other
sympathomimetics or vasodilators.
In animals treated with clenbuterol disturbances of the heart rhythm can be expected
upon anaesthesia.
Simultaneous administration of narcotics containing halogens (isoflurane,
methoxyflurane) increases the risk of ventricular arrhythmias.
During the use of both local and general anaesthetics one cannot exclude a further
vascular dilatation and fall of blood pressure, particularly if used in combination with
atropine.
Increased risk of arrhythmia with simultaneous administration of digitalis glycosides.
The veterinary medicinal product can reduce or neutralise the effects of
prostaglandin F2α and oxytocin on the uterus.
Clenbuterol hydrochloride is a
by β-blockers.

Do not store above 30 °C.

Meat and offal: 28 days
Do not use in animals producing milk for human consumption.

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.