Neutrophilia after Milbemycin Oxime (Interceptor) in dogs

56 reports to the FDA describe neutrophilia in dogs given Milbemycin Oxime. That is 0.2% of all reports for this medicine, compared with 0.6% across reports for all dog medicines, so it is reported less often than average with this medicine.

56Reports

48%Marked serious

1.8%Recovered

23%Died or euthanised

10 daysTypical onset

How soon it started

Same day

2 9.1%

1–2 days

6 27%

3–7 days

3 14%

1–4 weeks

4 18%

Over a month

7 32%

How the animals did

Recovered with lasting effects

1 1.8%

Still unwell when reported

19 34%

Died

8 14%

Euthanised

5 8.9%

Not known

23 41%

Problems reported at the same time

35 63%

31 55%

31 55%

31 55%

28 50%

20 36%

Abnormal radiograph finding

15 27%

Kidney problems

14 25%

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 neutrophilia in dogs?: 56 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 10 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 Ivermectin + Pyrantel (Heartgard Plus) 327 reports · 0.2% of its reports
Neutrophilia after Milbemycin Oxime + Spinosad (Trifexis) 440 reports · 0.3% of its reports
Neutrophilia after Moxidectin (ProHeart 6) 429 reports · 0.8% of its reports
Neutrophilia after Milbemycin Oxime + Praziquantel (Interceptor Plus) 133 reports · 0.4% of its reports
Neutrophilia after Selamectin (Revolution) 75 reports · 0.3% of its reports
Neutrophilia after Ivermectin (Heartgard) 69 reports · 0.6% of its reports
Neutrophilia after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 20 reports · 0.2% of its reports

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