Unable to stand after Milbemycin Oxime (Interceptor) in dogs

The FDA has received 28 reports of unable to stand in dogs after Milbemycin Oxime. That is 0.1% of all reports for this medicine, compared with 0.3% across reports for all dog medicines, so it is reported less often than average with this medicine.

28Reports

71%Marked serious

39%Recovered

7.1%Died or euthanised

13 daysTypical onset

How soon it started

Same day

2 12%

1–2 days

3 18%

3–7 days

2 12%

1–4 weeks

3 18%

Over a month

7 41%

How the animals did

Recovered

10 36%

Recovered with lasting effects

1 3.6%

Still unwell when reported

12 43%

Died

2 7.1%

Not known

3 11%

Problems reported at the same time

11 39%

11 39%

8 29%

6 21%

5 18%

4 14%

4 14%

4 14%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Milbemycin Oxime prevents heartworm and controls some intestinal worms (monthly).

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

Some herding breeds (for example Collies) carry the MDR1 gene variant and can be more sensitive to this drug class at high doses.

Questions owners ask

Can Milbemycin Oxime cause unable to stand in dogs?: 28 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 13 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).

Unable to stand with similar medicines

Unable to stand after Ivermectin + Pyrantel (Heartgard Plus) 198 reports · 0.1% of its reports
Unable to stand after Milbemycin Oxime + Spinosad (Trifexis) 419 reports · 0.3% of its reports
Unable to stand after Moxidectin (ProHeart 6) 132 reports · 0.3% of its reports
Unable to stand after Milbemycin Oxime + Praziquantel (Interceptor Plus) 76 reports · 0.2% of its reports
Unable to stand after Selamectin (Revolution) 39 reports · 0.1% of its reports
Unable to stand after Ivermectin (Heartgard) 67 reports · 0.6% of its reports

All reported side effects of Milbemycin Oxime in dogs · Medicines most reported with unable to stand