Skin redness after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) in dogs

The FDA has received 24 reports of skin redness in dogs after Moxidectin + Pyrantel + Sarolaner. That is 2.1% of all reports for this medicine, compared with 1.0% across reports for all dog medicines, so it is reported unusually often with this medicine.

24Reports

58%Marked serious

50%Recovered

4.2%Died or euthanised

29 daysTypical onset

How soon it started

Same day

2 13%

1–2 days

1 6.3%

3–7 days

0 0.0%

1–4 weeks

6 38%

Over a month

7 44%

How the animals did

Recovered

12 50%

Still unwell when reported

4 17%

Euthanised

1 4.2%

Not known

7 29%

Problems reported at the same time

Itching

10 42%

Hair loss

5 21%

Loss of appetite

4 17%

Swelling

4 17%

Vomiting

4 17%

Otitis externa

4 17%

Didn't work as expected

4 17%

Lethargy

3 13%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Moxidectin prevents heartworm disease (monthly topical, or a 6- or 12-month injection for dogs). Pyrantel treats roundworms and hookworms. Sarolaner kills fleas, ticks and some mites; monthly.

Products with this combination include Simparica Trio. 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 Moxidectin + Pyrantel + Sarolaner cause skin redness in dogs?: 24 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 29 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).

Skin redness with similar medicines

Skin redness after Ivermectin + Pyrantel (Heartgard Plus) 491 reports · 0.3% of its reports
Skin redness after Milbemycin Oxime + Spinosad (Trifexis) 828 reports · 0.6% of its reports
Skin redness after Moxidectin (ProHeart 6) 1,035 reports · 2.0% of its reports
Skin redness after Milbemycin Oxime + Praziquantel (Interceptor Plus) 163 reports · 0.5% of its reports
Skin redness after Milbemycin Oxime (Interceptor) 71 reports · 0.2% of its reports
Skin redness after Selamectin (Revolution) 365 reports · 1.2% of its reports
Skin redness after Ivermectin (Heartgard) 105 reports · 0.9% of its reports

All reported side effects of Moxidectin + Pyrantel + Sarolaner in dogs · Medicines most reported with skin redness