Kidney problems after Milbemycin Oxime + Spinosad (Trifexis) in dogs

The FDA has received 865 reports of kidney problems in dogs after Milbemycin Oxime + Spinosad. That is 0.7% of all reports for this medicine, compared with 2.4% across reports for all dog medicines, so it is reported less often than average with this medicine.

865Reports

82%Marked serious

24%Recovered

35%Died or euthanised

23 daysTypical onset

How soon it started

Same day

146 28%

1–2 days

55 11%

3–7 days

25 4.8%

1–4 weeks

49 9.4%

Over a month

245 47%

How the animals did

Recovered

68 7.9%

Recovered with lasting effects

140 16%

Still unwell when reported

180 21%

Died

143 17%

Euthanised

156 18%

Not known

178 21%

Problems reported at the same time

376 43%

360 42%

326 38%

326 38%

294 34%

185 21%

138 16%

137 16%

Age of the animals

Under 1 year

1–3 years

140

4–7 years

187

8–11 years

224

12+ years

230

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 kidney problems in dogs?: 865 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 23 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).

Kidney problems with similar medicines

Kidney problems after Ivermectin + Pyrantel (Heartgard Plus) 619 reports · 0.4% of its reports
Kidney problems after Moxidectin (ProHeart 6) 840 reports · 1.7% of its reports
Kidney problems after Milbemycin Oxime + Praziquantel (Interceptor Plus) 256 reports · 0.8% of its reports
Kidney problems after Milbemycin Oxime (Interceptor) 243 reports · 0.8% of its reports
Kidney problems after Selamectin (Revolution) 257 reports · 0.9% of its reports
Kidney problems after Ivermectin (Heartgard) 187 reports · 1.6% of its reports
Kidney problems after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 37 reports · 0.4% of its reports
Kidney problems after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 26 reports · 2.2% of its reports

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