Seizures after Trilostane (Vetoryl) in dogs

The FDA has received 367 reports of seizures in dogs after Trilostane. That is 3.1% of all reports for this medicine, compared with 4.4% across reports for all dog medicines.

367Reports

77%Marked serious

20%Recovered

26%Died or euthanised

25 daysTypical onset

How soon it started

Same day

26 10%

1–2 days

24 9.4%

3–7 days

28 11%

1–4 weeks

63 25%

Over a month

115 45%

How the animals did

Recovered

71 19%

Recovered with lasting effects

3 0.8%

Still unwell when reported

58 16%

Died

31 8.4%

Euthanised

66 18%

Not known

138 38%

Problems reported at the same time

97 26%

79 22%

76 21%

69 19%

53 14%

50 14%

42 11%

41 11%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

155

12+ years

180

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 seizures in dogs?: 367 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 25 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).

Seizures with similar medicines

Seizures after Insulin 396 reports · 5.4% of its reports
Seizures after Phenylpropanolamine (Proin) 195 reports · 4.7% of its reports
Seizures after Levothyroxine 206 reports · 6.8% of its reports

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