Didn't work as expected after Butorphanol in horses

The FDA has received 84 reports of didn't work as expected in horses after Butorphanol. That is 28% of all reports for this medicine, compared with 23% across reports for all horse medicines.

84Reports

45%Marked serious

57%Recovered

3.6%Died or euthanised

Same dayTypical onset

How soon it started

Same day

47 94%

1–2 days

0 0.0%

3–7 days

1 2.0%

1–4 weeks

0 0.0%

Over a month

2 4.0%

How the animals did

Recovered

48 57%

Still unwell when reported

1 1.2%

Died

2 2.4%

Euthanised

1 1.2%

Not known

32 38%

Problems reported at the same time

Underdose

17 20%

Intentional misuse

6 7.1%

Drug administration error

3 3.6%

Death

2 2.4%

Administration error

2 2.4%

Behaviour change

1 1.2%

Paddling

1 1.2%

Prolonged anaesthesia

1 1.2%

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 didn't work as expected in horses?: 84 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 the same 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).

Didn't work as expected with similar medicines

Didn't work as expected after Omeprazole 1,708 reports · 88% of its reports
Didn't work as expected after Pergolide 143 reports · 12% of its reports
Didn't work as expected after Ceftiofur 64 reports · 5.3% of its reports
Didn't work as expected after Detomidine 306 reports · 31% of its reports
Didn't work as expected after Flunixin Meglumine 46 reports · 7.4% of its reports
Didn't work as expected after Ketamine 463 reports · 82% of its reports
Didn't work as expected after Polysulfated Glycosaminoglycan 40 reports · 7.8% of its reports
Didn't work as expected after Xylazine 268 reports · 58% of its reports
Didn't work as expected after Sucralfate 384 reports · 98% of its reports
Didn't work as expected after Ponazuril 48 reports · 27% of its reports

All reported side effects of Butorphanol in horses · Medicines most reported with didn't work as expected