Vomiting after Milbemycin Oxime (Interceptor) in dogs

The FDA has received 4,379 reports of vomiting in dogs after Milbemycin Oxime. That is 15% of all reports for this medicine, compared with 28% across reports for all dog medicines, so it is reported less often than average with this medicine.

4,379Reports

8.4%Marked serious

28%Recovered

4.5%Died or euthanised

1 daysTypical onset

How soon it started

Same day

549 43%

1–2 days

116 9.1%

3–7 days

42 3.3%

1–4 weeks

85 6.7%

Over a month

482 38%

How the animals did

Recovered

1,203 27%

Recovered with lasting effects

22 0.5%

Still unwell when reported

263 6.0%

Died

155 3.5%

Euthanised

40 0.9%

Not known

2,696 62%

Problems reported at the same time

1,042 24%

888 20%

638 15%

335 7.7%

194 4.4%

182 4.2%

Didn't work as expected

169 3.9%

Wobbliness (ataxia)

161 3.7%

Age of the animals

Under 1 year

836

1–3 years

1,478

4–7 years

1,087

8–11 years

595

12+ years

247

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 vomiting in dogs?: 4,379 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 1 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).

Vomiting with similar medicines

Vomiting after Ivermectin + Pyrantel (Heartgard Plus) 20,052 reports · 14% of its reports
Vomiting after Milbemycin Oxime + Spinosad (Trifexis) 75,323 reports · 58% of its reports
Vomiting after Moxidectin (ProHeart 6) 12,413 reports · 25% of its reports
Vomiting after Milbemycin Oxime + Praziquantel (Interceptor Plus) 7,113 reports · 23% of its reports
Vomiting after Selamectin (Revolution) 3,074 reports · 10% of its reports
Vomiting after Ivermectin (Heartgard) 3,182 reports · 26% of its reports
Vomiting after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 3,567 reports · 42% of its reports
Vomiting after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 197 reports · 17% of its reports
Vomiting after Ivermectin + Praziquantel 40 reports · 20% of its reports
Vomiting after Eprinomectin 20 reports · 19% of its reports

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