Nystagmus after Trilostane (Vetoryl) in dogs

The FDA has received 34 reports of nystagmus in dogs after Trilostane. That is 0.3% of all reports for this medicine, compared with 0.3% across reports for all dog medicines.

34Reports

65%Marked serious

21%Recovered

24%Died or euthanised

43 daysTypical onset

How soon it started

Same day

0 0.0%

1–2 days

3 10%

3–7 days

5 17%

1–4 weeks

4 14%

Over a month

17 59%

How the animals did

Recovered

6 18%

Recovered with lasting effects

1 2.9%

Still unwell when reported

1 2.9%

Died

2 5.9%

Euthanised

6 18%

Not known

18 53%

Problems reported at the same time

Wobbliness (ataxia)

13 38%

Liver problems

13 38%

Head tilt - ear disorder

10 29%

10 29%

8 24%

7 21%

7 21%

7 21%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Trilostane treats Cushing's disease (an overactive adrenal gland).

Products with this ingredient include Vetoryl. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Questions owners ask

Can Trilostane cause nystagmus in dogs?: 34 reports link the two, but a report alone does not prove the medicine was the cause: other illnesses, other medicines or coincidence can be involved. Your vet can judge it for your animal.
How soon after a dose was it reported?: In half of the reports with dates, it started within 43 days of the first dose.
What should I do?: Don't give another dose until you've spoken to your vet, and keep the packaging so you can tell them the product and dose. Your vet can also report it to the FDA (or you can, through the manufacturer or FDA form 1932a).

Nystagmus with similar medicines

Nystagmus after Phenylpropanolamine (Proin) 20 reports · 0.5% of its reports

All reported side effects of Trilostane in dogs · Medicines most reported with nystagmus