Falling after Milbemycin Oxime + Spinosad (Trifexis) in dogs

393 reports to the FDA describe falling in dogs given Milbemycin Oxime + Spinosad. That is 0.3% of all reports for this medicine, compared with 0.4% across reports for all dog medicines.

393Reports

65%Marked serious

52%Recovered

16%Died or euthanised

2 daysTypical onset

How soon it started

Same day

120 39%

1–2 days

36 12%

3–7 days

11 3.6%

1–4 weeks

38 13%

Over a month

99 33%

How the animals did

Recovered

161 41%

Recovered with lasting effects

44 11%

Still unwell when reported

56 14%

Died

30 7.6%

Euthanised

32 8.1%

Not known

70 18%

Problems reported at the same time

146 37%

141 36%

105 27%

105 27%

97 25%

86 22%

79 20%

61 16%

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 falling in dogs?: 393 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 2 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).

Falling with similar medicines

Falling after Ivermectin + Pyrantel (Heartgard Plus) 312 reports · 0.2% of its reports
Falling after Moxidectin (ProHeart 6) 117 reports · 0.2% of its reports
Falling after Milbemycin Oxime + Praziquantel (Interceptor Plus) 121 reports · 0.4% of its reports
Falling after Milbemycin Oxime (Interceptor) 40 reports · 0.1% of its reports
Falling after Selamectin (Revolution) 36 reports · 0.1% of its reports
Falling after Ivermectin (Heartgard) 75 reports · 0.6% of its reports

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