Swelling after Mirtazapine (Mirataz) in cats

The FDA has received 57 reports of swelling in cats after Mirtazapine. That is 3.0% of all reports for this medicine, compared with 1.9% across reports for all cat medicines, so it is reported unusually often with this medicine.

57Reports

72%Marked serious

14%Recovered

44%Died or euthanised

3 daysTypical onset

How soon it started

Same day

17 30%

1–2 days

11 19%

3–7 days

11 19%

1–4 weeks

8 14%

Over a month

10 18%

How the animals did

Recovered

8 14%

Still unwell when reported

10 18%

Died

12 21%

Euthanised

13 23%

Not known

14 25%

Problems reported at the same time

28 49%

24 42%

18 32%

17 30%

9 16%

9 16%

9 16%

Application site reaction

9 16%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Mirtazapine stimulates appetite (cats: ointment applied to the ear).

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

Questions owners ask

Can Mirtazapine cause swelling in cats?: 57 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).

Swelling with similar medicines

Swelling after Maropitant (Cerenia) 147 reports · 3.8% of its reports

All reported side effects of Mirtazapine in cats · Medicines most reported with swelling