Clodronate
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Clodronic acid (INN) or clodronate disodium (USAN) is a first generation (non-nitrogenous) bisphosphonate. It is an anti-osteoporotic drug approved for the prevention and treatment of osteoporosis in post-menopausal women and men to reduce vertebral fractures, hyperparathyroidism, hypercalcemia in malignancy, multiple myeloma and fracture related pain because of its potent anti-inflammatory and analgesic effects shown as a reduction in inflammatory markers like IL-1β, IL-6, and TNF-alfa.
An Italian study compared the analgesic effect of clodronic acid versus acetaminophen in reumatic condition related pain. Study result show a reduction in pain in favor of clodronic acid that provided more analgesia than 3 grams/day of acetaminophen. Clodronate is also used in experimental medicine to selectively deplete macrophages.
Clodronic acid is approved for human use in Canada and Australia, the United Kingdom, where it is marketed as Bonefos, Loron, Clodron and in Italy as Clasteon, Difosfonal, Osteostab and several generics. In other countries is prescribed as a bone resorption inhibitor and antihypercalcemic agent.
Use in equine medicine
Clodronic acid is approved for use in horses under the trade name Osphos, for treatment of navicular syndrome. It is given by intramuscular injection, with the total dose divided into 3 sites on the horse. Clinical effects may not be seen for up to 2 months, and horses may need treatments repeated every 3 to 6 months.
Adverse reactions and contraindications
Osphos has been shown to have several adverse effects. These include:
- Signs of discomfort, agitation, or colic, usually within 2 hours of treatment.
- Head shaking
- Lip licking
References
© 2026 MyEClinic – IFTM Institut für Telematik in der Medizin GmbH
