Anisocoria after Maropitant (Cerenia) in dogs

The FDA has received 31 reports of anisocoria in dogs after Maropitant. That is 0.3% of all reports for this medicine, compared with 0.0% across reports for all dog medicines, so it is reported unusually often with this medicine.

31Reports

90%Marked serious

16%Recovered

29%Died or euthanised

1 daysTypical onset

How soon it started

Same day

12 44%

1–2 days

4 15%

3–7 days

4 15%

1–4 weeks

6 22%

Over a month

1 3.7%

How the animals did

Recovered

5 16%

Still unwell when reported

15 48%

Died

4 13%

Euthanised

5 16%

Not known

2 6.5%

Problems reported at the same time

14 45%

14 45%

11 35%

10 32%

9 29%

9 29%

7 23%

7 23%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Maropitant prevents vomiting and motion sickness.

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

Questions owners ask

Can Maropitant cause anisocoria in dogs?: 31 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 1 day 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).

All reported side effects of Maropitant in dogs · Medicines most reported with anisocoria