Hypoalbuminaemia after Milbemycin Oxime + Spinosad (Trifexis) in dogs

The FDA has received 179 reports of hypoalbuminaemia in dogs after Milbemycin Oxime + Spinosad. That is 0.1% 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.

179Reports

87%Marked serious

28%Recovered

36%Died or euthanised

20 daysTypical onset

How soon it started

Same day

30 24%

1–2 days

16 13%

3–7 days

10 7.9%

1–4 weeks

18 14%

Over a month

52 41%

How the animals did

Recovered

27 15%

Recovered with lasting effects

24 13%

Still unwell when reported

33 18%

Died

25 14%

Euthanised

40 22%

Not known

30 17%

Problems reported at the same time

103 58%

103 58%

92 51%

89 50%

68 38%

65 36%

65 36%

62 35%

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 hypoalbuminaemia in dogs?: 179 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 20 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).

Hypoalbuminaemia with similar medicines

Hypoalbuminaemia after Ivermectin + Pyrantel (Heartgard Plus) 144 reports · 0.1% of its reports
Hypoalbuminaemia after Moxidectin (ProHeart 6) 303 reports · 0.6% of its reports
Hypoalbuminaemia after Milbemycin Oxime + Praziquantel (Interceptor Plus) 57 reports · 0.2% of its reports
Hypoalbuminaemia after Milbemycin Oxime (Interceptor) 66 reports · 0.2% of its reports
Hypoalbuminaemia after Selamectin (Revolution) 71 reports · 0.2% of its reports
Hypoalbuminaemia after Ivermectin (Heartgard) 54 reports · 0.4% of its reports

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