Vocalising after Milbemycin Oxime + Spinosad (Trifexis) in dogs

The FDA has received 1,251 reports of vocalising in dogs after Milbemycin Oxime + Spinosad. That is 1.0% of all reports for this medicine, compared with 1.2% across reports for all dog medicines.

1,251Reports

37%Marked serious

54%Recovered

12%Died or euthanised

1 daysTypical onset

How soon it started

Same day

476 49%

1–2 days

109 11%

3–7 days

37 3.8%

1–4 weeks

62 6.4%

Over a month

292 30%

How the animals did

Recovered

540 43%

Recovered with lasting effects

140 11%

Still unwell when reported

146 12%

Died

104 8.3%

Euthanised

50 4.0%

Not known

271 22%

Problems reported at the same time

597 48%

389 31%

334 27%

323 26%

308 25%

152 12%

147 12%

146 12%

Age of the animals

Under 1 year

276

1–3 years

408

4–7 years

298

8–11 years

150

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 vocalising in dogs?: 1,251 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).

Vocalising with similar medicines

Vocalising after Ivermectin + Pyrantel (Heartgard Plus) 694 reports · 0.5% of its reports
Vocalising after Moxidectin (ProHeart 6) 390 reports · 0.8% of its reports
Vocalising after Milbemycin Oxime + Praziquantel (Interceptor Plus) 212 reports · 0.7% of its reports
Vocalising after Milbemycin Oxime (Interceptor) 161 reports · 0.5% of its reports
Vocalising after Selamectin (Revolution) 247 reports · 0.8% of its reports
Vocalising after Ivermectin (Heartgard) 173 reports · 1.4% of its reports
Vocalising after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 58 reports · 0.7% of its reports
Vocalising after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 29 reports · 2.5% of its reports

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