Reddening of the skin after Moxidectin (ProHeart 6) in dogs

485 reports to the FDA describe reddening of the skin in dogs given Moxidectin. That is 1.0% of all reports for this medicine, compared with 0.4% across reports for all dog medicines, so it is reported unusually often with this medicine.

485Reports

69%Marked serious

39%Recovered

0.4%Died or euthanised

Same dayTypical onset

How soon it started

Same day

421 89%

1–2 days

19 4.0%

3–7 days

14 3.0%

1–4 weeks

7 1.5%

Over a month

13 2.7%

How the animals did

Recovered

190 39%

Recovered with lasting effects

1 0.2%

Still unwell when reported

264 54%

Died

2 0.4%

Not known

28 5.8%

Problems reported at the same time

330 68%

274 56%

254 52%

135 28%

106 22%

77 16%

74 15%

50 10%

Age of the animals

Under 1 year

1–3 years

272

4–7 years

135

8–11 years

12+ years

About this medicine

Moxidectin prevents heartworm disease (monthly topical, or a 6- or 12-month injection for dogs).

Products with this ingredient include ProHeart 6, ProHeart 12. 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 cause reddening of the skin in dogs?: 485 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 the same 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).

Reddening of the skin with similar medicines

Reddening of the skin after Ivermectin + Pyrantel (Heartgard Plus) 173 reports · 0.1% of its reports
Reddening of the skin after Milbemycin Oxime + Spinosad (Trifexis) 729 reports · 0.6% of its reports
Reddening of the skin after Milbemycin Oxime + Praziquantel (Interceptor Plus) 101 reports · 0.3% of its reports
Reddening of the skin after Selamectin (Revolution) 51 reports · 0.2% of its reports
Reddening of the skin after Ivermectin (Heartgard) 32 reports · 0.3% of its reports

All reported side effects of Moxidectin in dogs · Medicines most reported with reddening of the skin