1. Trilostane is too new, has a much shorter track record than Lysodren, and vets are not as familiar with it.

While that may be true in the US it is not worldwide and there are numerous publications showing it to be safe and effective. Some bias I think since it was no initially developed in the US.

2. Pups on Trilo seem to have inappetence issues; some fairly quickly, some after being on it for a time.

If you look at the data with respect to op-DDD and trilostane inappetance can occur with both and is usually less frequent, less severe and more rapidly reversed with trilostane.

3. Smaller pups seem to have more issues than larger dogs.

This is simply a dosing issue and occurs with many types of drugs. When you say pups are you referring to puppies as there would be little reason to use either medication in very young animals.

4. Some pups seem to experience a rapid drop in cortisol resulting in an apparent crash when first starting Trilo.

Same as can be seen with trilostane, ketoconazole or op-ddd.

5. Shaking and muscle weakness either increases or suddenly appears after starting Trilo.

Again the data does not support this.

6. The attitude that Trilo is a "safe" drug with no side effects.

It is safe. Thats it was approved. Does it have side effects? Yes, and those are clearly listed on the package insert and in scientific publications.


Finally, why are Trilostane and Anipryl the only drugs approved to treat canine Cushing's? Lysodren has been around and in use much longer, yet has not been approved.

No one has tried to get op-DDD approved for use in the dog. I doubt anyone will as there would be huge hurdles to overcome given its derivation (op-DDT), manufacturing issues, safety profile and the availability of other drugs with equal efficacy and higher safety.


David Bruyette DVM DACVIM