Q. 16 year old cat has kidney disease but is aggressive with another cat . Are there any contraindications for doing a trial of Amitriptyline with him?
JESSICA L DESROSIERS
A. Amitriptyline can sometimes cause adverse reactions in the heart, kidney or liver, especially in cats with kidney or liver disease. It is best to contact your vet first and see if they feel comfortable giving a trial dose of the medication. Your vet may wish to monitor your cat's bloodwork during this time to watch for any adverse effects.
There are other products available that may also help such as Feli-way which is a wall plug-in (or collar) that releases a natural pheromone to calm cats and is commonly used for inter-cat aggression. As the product is not ingested it may be safer to use on a cat with underlying health conditions.