Skin disorders after Milbemycin Oxime (Interceptor) in dogs

The FDA has received 35 reports of skin disorders in dogs after Milbemycin Oxime. That is 0.1% of all reports for this medicine, compared with 0.5% across reports for all dog medicines, so it is reported less often than average with this medicine.

35Reports

23%Marked serious

2.9%Recovered

11%Died or euthanised

93 daysTypical onset

How soon it started

Same day

3 14%

1–2 days

0 0.0%

3–7 days

1 4.5%

1–4 weeks

4 18%

Over a month

14 64%

How the animals did

Recovered

1 2.9%

Still unwell when reported

11 31%

Died

2 5.7%

Euthanised

2 5.7%

Not known

19 54%

Problems reported at the same time

7 20%

5 14%

4 11%

4 11%

4 11%

4 11%

Didn't work as expected

4 11%

Weight loss

3 8.6%

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 skin disorders in dogs?: 35 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 93 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).

Skin disorders with similar medicines

Skin disorders after Ivermectin + Pyrantel (Heartgard Plus) 153 reports · 0.1% of its reports
Skin disorders after Milbemycin Oxime + Spinosad (Trifexis) 576 reports · 0.4% of its reports
Skin disorders after Moxidectin (ProHeart 6) 50 reports · 0.1% of its reports
Skin disorders after Milbemycin Oxime + Praziquantel (Interceptor Plus) 118 reports · 0.4% of its reports
Skin disorders after Selamectin (Revolution) 42 reports · 0.1% of its reports
Skin disorders after Ivermectin (Heartgard) 47 reports · 0.4% of its reports

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