Neutrophilia after Butorphanol in cats

The FDA has received 29 reports of neutrophilia in cats after Butorphanol. That is 1.3% of all reports for this medicine, compared with 0.7% across reports for all cat medicines, so it is reported unusually often with this medicine.

29Reports

76%Marked serious

17%Recovered

34%Died or euthanised

2 daysTypical onset

How soon it started

Same day

12 46%

1–2 days

4 15%

3–7 days

5 19%

1–4 weeks

4 15%

Over a month

1 3.8%

How the animals did

Recovered

4 14%

Recovered with lasting effects

1 3.4%

Still unwell when reported

12 41%

Died

2 6.9%

Euthanised

8 28%

Not known

2 6.9%

Problems reported at the same time

18 62%

16 55%

16 55%

13 45%

12 41%

12 41%

11 38%

10 34%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Type: medicine.

Questions owners ask

Can Butorphanol cause neutrophilia in cats?: 29 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 2 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).

Neutrophilia with similar medicines

Neutrophilia after Ketamine 23 reports · 0.7% of its reports
Neutrophilia after Isoflurane 28 reports · 1.4% of its reports
Neutrophilia after Methylprednisolone 42 reports · 2.6% of its reports
Neutrophilia after Vitamin B12 20 reports · 5.2% of its reports

All reported side effects of Butorphanol in cats · Medicines most reported with neutrophilia