Licking after Milbemycin Oxime + Spinosad (Trifexis) in dogs

222 reports to the FDA describe licking in dogs given Milbemycin Oxime + Spinosad. That is 0.2% of all reports for this medicine, compared with 0.2% across reports for all dog medicines.

222Reports

22%Marked serious

44%Recovered

3.2%Died or euthanised

1 daysTypical onset

How soon it started

Same day

69 43%

1–2 days

19 12%

3–7 days

9 5.7%

1–4 weeks

14 8.8%

Over a month

48 30%

How the animals did

Recovered

38 17%

Recovered with lasting effects

60 27%

Still unwell when reported

45 20%

Died

5 2.3%

Euthanised

2 0.9%

Not known

72 32%

Problems reported at the same time

Itching

73 33%

Vomiting

59 27%

Lethargy

57 26%

Skin rash or irritation

39 18%

Loss of appetite

37 17%

Hair loss

33 15%

Behaviour change

31 14%

Reddening of the skin

26 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). Spinosad kills fleas; monthly chewable.

Products with this combination include Trifexis. 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 + Spinosad cause licking in dogs?: 222 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).

Licking with similar medicines

Licking after Ivermectin + Pyrantel (Heartgard Plus) 172 reports · 0.1% of its reports
Licking after Moxidectin (ProHeart 6) 44 reports · 0.1% of its reports
Licking after Milbemycin Oxime + Praziquantel (Interceptor Plus) 102 reports · 0.3% of its reports
Licking after Selamectin (Revolution) 27 reports · 0.1% of its reports
Licking after Ivermectin (Heartgard) 29 reports · 0.2% of its reports

All reported side effects of Milbemycin Oxime + Spinosad in dogs · Medicines most reported with licking