Lymphopenia after Maropitant (Cerenia) in dogs

The FDA has received 250 reports of lymphopenia in dogs after Maropitant. That is 2.1% of all reports for this medicine, compared with 0.3% across reports for all dog medicines, so it is reported unusually often with this medicine.

250Reports

85%Marked serious

9.2%Recovered

40%Died or euthanised

3 daysTypical onset

How soon it started

Same day

39 19%

1–2 days

56 27%

3–7 days

31 15%

1–4 weeks

27 13%

Over a month

55 26%

How the animals did

Recovered

22 8.8%

Recovered with lasting effects

1 0.4%

Still unwell when reported

98 39%

Died

38 15%

Euthanised

61 24%

Not known

30 12%

Problems reported at the same time

164 66%

150 60%

148 59%

148 59%

97 39%

96 38%

95 38%

94 38%

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 lymphopenia in dogs?: 250 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 3 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).

Lymphopenia with similar medicines

Lymphopenia after Capromorelin (Entyce) 45 reports · 3.0% of its reports

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