Pain after Milbemycin Oxime (Interceptor) in dogs

The FDA has received 121 reports of pain in dogs after Milbemycin Oxime. That is 0.4% of all reports for this medicine, compared with 0.7% across reports for all dog medicines, so it is reported less often than average with this medicine.

121Reports

28%Marked serious

14%Recovered

11%Died or euthanised

26 daysTypical onset

How soon it started

Same day

8 24%

1–2 days

3 8.8%

3–7 days

2 5.9%

1–4 weeks

5 15%

Over a month

16 47%

How the animals did

Recovered

16 13%

Recovered with lasting effects

1 0.8%

Still unwell when reported

22 18%

Died

10 8.3%

Euthanised

3 2.5%

Not known

69 57%

Problems reported at the same time

52 43%

40 33%

23 19%

20 17%

19 16%

18 15%

17 14%

14 12%

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 pain in dogs?: 121 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 26 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).

Pain with similar medicines

Pain after Ivermectin + Pyrantel (Heartgard Plus) 330 reports · 0.2% of its reports
Pain after Milbemycin Oxime + Spinosad (Trifexis) 572 reports · 0.4% of its reports
Pain after Moxidectin (ProHeart 6) 436 reports · 0.9% of its reports
Pain after Milbemycin Oxime + Praziquantel (Interceptor Plus) 129 reports · 0.4% of its reports
Pain after Selamectin (Revolution) 159 reports · 0.5% of its reports
Pain after Ivermectin (Heartgard) 63 reports · 0.5% of its reports

All reported side effects of Milbemycin Oxime in dogs · Medicines most reported with pain