Dosage and Usage


Cartrophen Vet has an optimal clinical efficacy in dogs at 3mg/kg of pentosan polysulfate sodium (PPS) administered sub-cutaneously on four occasions at intervals of 5-7 days. In the horse the recommended dosage is slightly lower at 2-2.5mg/kg of PPS administered by way of intramuscular injection on four occasions at intervals of 5-7 days. The dosage is equivalent to 1g of PPS per 400-500kg horse or the equivalent of a bottle of Cartrophen Vet (10mL) or Cartrophen Equine Forte (4mL), which contain 1g of PPS.

Dose response studies in dogs with OA have demonstrated that 3mg/kg of Cartrophen Vet was optimal and both 1mg/kg and 5mg/kg were not as effective. The lameness index was measured on a 5-point scale of severity (from “no lameness” to “will not use”) and showed a decrease after the four weekly injections that was maintained four weeks after treatment (eighth week). The efficacy index was the number of significant changes in clinical status in each group when compared to base line values. Higher dosages showed a diminished efficacy, which was not a toxic effect, but rather a shift to a less favourable balance of anti-catabolic and pro-catabolic activities where the overall tissue effect is less favourable.

Cartrophen Vet dose chart – Download Dose chart


Dosing Regimen

All dogs treated with Cartrophen Vet will require a minimum of 1 full course per year. It is also recommended an OA check-up be performed at least every 6 months after OA has been diagnosed, essential to monitor progress and keep the disease under control and in order to determine the best time to repeat. Treatment is based on each individual patient and the objective is to prevent signs from recurring by stopping or slowing disease development.

Veterinary experience shows that clinical response generally lasts between 3 – 12 months and each patient should be assessed on an individual basis. While it will vary from case to case, from clinical experience, below are approximate recommended regimens.

  • Mild signs of OA – 1 course* every 12 months
  • Moderate signs of OA – 1 course* every 6 months (2 courses per 12 months)
  • Chronic and severe signs of OA – 1 course* every 4 months (3 courses per 12 months)
    * course = administration every 5-7 days on four occasions.


Click to view references

Read RA, Cullis-Hill D, Jones MP (1996) Systemic use of pentosan polysulphate in the treatment of osteoarthritis. J Small Animal Practice 37:108-114

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