POM-V Prescription Required

Osphos 51 mg/ml Solution for Injection for Horses

Active ingredient: Clodronic Acid

Form

Injection

Species

Horses

Manufacturer

Dechra Regulatory B.V.

VMD MA No.

50406/3041

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 Clodronic Acid

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.

Your prescription rights → VMD register of retailers →

Prescription required

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

Clinical information

Osphos 51 mg/ml Solution for Injection for Horses — SPC Details

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

medicinal product per 100 kg body weight. Divide the total volume evenly for
administration at 2 to 3 separate injection sites.
The maximum dose is 765 mg clodronic acid per horse (one 15 ml vial per horse
>500 kg). Do not exceed the recommended dose.
To ensure a correct dosage, body weight should be determined as accurately as
possible.

Do not use in horses less than 4 years of age, due to the absence of data regarding
use in growing animals.
Do not use in horses with impaired renal function.
Do not use in cases of hypersensitivity to the active substance or to any of the
excipients.
Do not administer intravenously.

Horses:
Common
(1 to 10 animals / 100 animals
treated):
Nervous
Lip licking, Colic
Increased yawning
Uncommon
(1 to 10 animals / 1,000 animals
treated):
Head bobbing
Injection site swelling
a
, Injection site pain
a
Pawing
Hives
Pruritus
RareRenal insufficiency
b
(1 to 10 animals / 10,000
animals treated):
a
Transient.
b
More frequently observed in animals concurrently exposed to NSAIDs. In these
cases, appropriate fluid therapy should be instituted and renal parameters monitored.
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.

The veterinary medicinal product should be used only after a proper diagnosis
combining a complete orthopaedic clinical examination including local analgesia and
appropriate imaging techniques, in order to identify the cause of pain and the nature
of bone lesions.
Clinical improvement in lameness grade may not be accompanied by radiographic
changes in the appearance of the navicular bone.

Special precautions for safe use in the target species:
Use caution when administering bisphosphonates to horses with conditions affecting
mineral or electrolyte homeostasis, e.g. hyperkalaemic periodic paralysis,
hypocalcaemia.
Adequate access to drinking water should be provided when using the veterinary
medicinal product. If uncertainty exists about renal function, renal parameters should
be assessed before administration of the veterinary medicinal product. Water
consumption and urine output should be monitored after administration.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
Accidental self-injection of this veterinary medicinal product may increase the risk of
obstructed labour in pregnant women and affect fertility in men.
Care should be taken when handling the veterinary medicinal product to avoid self-
injection.
In case of accidental self-injection, seek medical advice immediately and show the
package leaflet or the label to the physician.
Special precautions for the protection of the environment:
Not applicable.

Medications such as aminoglycosides whose toxicity can be exacerbated by a
reduction in serum calcium, and medications such as tetracyclines that can reduce
serum calcium should not be given for 72 hours after administration of clodronic acid.
Concurrent administration of potentially nephrotoxic drugs, such as NSAIDs, should
be approached with caution and renal function should be monitored.

Do not store above 30 C.
Keep the container in the outer carton.

Meat and offal: Zero days.
Not authorised for use in animals producing milk for human consumption.
4.

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.