Skin redness after Ivermectin (Heartgard) in dogs

105 reports to the FDA describe skin redness in dogs given Ivermectin. That is 0.9% of all reports for this medicine, compared with 1.0% across reports for all dog medicines.

105Reports

48%Marked serious

33%Recovered

9.5%Died or euthanised

16 daysTypical onset

How soon it started

Same day

16 23%

1–2 days

11 15%

3–7 days

5 7.0%

1–4 weeks

10 14%

Over a month

29 41%

How the animals did

Recovered

21 20%

Recovered with lasting effects

14 13%

Still unwell when reported

24 23%

Died

6 5.7%

Euthanised

4 3.8%

Not known

36 34%

Problems reported at the same time

31 30%

30 29%

29 28%

21 20%

21 20%

Skin rash or irritation

19 18%

Eye or vision problems

14 13%

Wobbliness (ataxia)

14 13%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Ivermectin prevents heartworm disease (monthly).

Products with this ingredient include Heartgard. 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 Ivermectin cause skin redness in dogs?: 105 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 16 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 Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 24 reports · 2.1% of its reports

All reported side effects of Ivermectin in dogs · Medicines most reported with skin redness