Bacterial skin infection after Ivermectin (Heartgard) in dogs

The FDA has received 27 reports of bacterial skin infection in dogs after Ivermectin. That is 0.2% of all reports for this medicine, compared with 0.1% across reports for all dog medicines, so it is reported unusually often with this medicine.

27Reports

44%Marked serious

15%Recovered

15%Died or euthanised

122 daysTypical onset

How soon it started

Same day

5 36%

1–2 days

1 7.1%

3–7 days

0 0.0%

1–4 weeks

0 0.0%

Over a month

8 57%

How the animals did

Recovered

3 11%

Recovered with lasting effects

1 3.7%

Still unwell when reported

10 37%

Died

2 7.4%

Euthanised

2 7.4%

Not known

9 33%

Problems reported at the same time

Vomiting

8 30%

Hair loss

8 30%

Itching

7 26%

Skin rash or irritation

7 26%

Didn't work as expected

6 22%

Loss of appetite

5 19%

Skin redness

5 19%

Swelling

5 19%

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 bacterial skin infection in dogs?: 27 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 122 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).

Bacterial skin infection with similar medicines

Bacterial skin infection after Ivermectin + Pyrantel (Heartgard Plus) 51 reports · 0.0% of its reports
Bacterial skin infection after Milbemycin Oxime + Spinosad (Trifexis) 180 reports · 0.1% of its reports
Bacterial skin infection after Moxidectin (ProHeart 6) 25 reports · 0.0% of its reports
Bacterial skin infection after Milbemycin Oxime + Praziquantel (Interceptor Plus) 40 reports · 0.1% of its reports
Bacterial skin infection after Selamectin (Revolution) 22 reports · 0.1% of its reports

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