Cartrophen Vet is contra-indicated for the treatment of septic arthritis. In this case, appropriate antimicrobial therapy should be instigated.

Cartrophen Vet has an effect on blood coagulation due to its fibrinolytic activity that lasts for up to 6–8 hours after administration. This is of no clinical significance in the normal dog.

Do not use in dogs with uncontrolled bleeding, trauma, infection, advanced liver or kidney impairment and cancer, especially haemangiosarcoma. It has been reported that a dog which had suffered pulmonary lacerations twelve months previously had severe pulmonary bleeding after an injection of Cartrophen Vet. Use with caution in dogs with a history of pulmonary lacerations.

Rarely, reaction to the injection may occur within 24 hours in an apparently healthy animal. In these circumstances treatment should be discontinued and symptomatic relief given. Because of the fibrinolytic action of Cartrophen Vet, the possibility of internal bleeding from a tumour or vascular abnormality should be considered and appropriate therapeutic action taken. It is recommended that the PCV and capillary filling time should be monitored.

NSAIDs and in particular aspirin should not be used in combination with Cartrophen Vet as they may affect thrombocyte adhesion and potentiate the anticoagulant activity of Cartrophen Vet. Corticosteroids have been shown to be antagonistic to a number of actions of Cartrophen Vet. Furthermore, use of anti-inflammatory drugs may result in a premature increase in the dog's activity which may interfere with the disease-modifying activity of Cartrophen Vet.

Do not use concurrently with steroids or non-steroidal anti-inflammatory drugs, including aspirin and phenylbutazone, or within 24 hours of such administration.

Occasional emesis may occur following injection.