Excessive licking and/or grooming after Ivermectin + Pyrantel (Heartgard Plus) in dogs

The FDA has received 80 reports of excessive licking and/or grooming in dogs after Ivermectin + Pyrantel. That is 0.1% of all reports for this medicine, compared with 0.1% across reports for all dog medicines, so it is reported less often than average with this medicine.

80Reports

26%Marked serious

10%Recovered

3.8%Died or euthanised

14 daysTypical onset

How soon it started

Same day

4 21%

1–2 days

3 16%

3–7 days

2 11%

1–4 weeks

4 21%

Over a month

6 32%

How the animals did

Recovered

8 10%

Still unwell when reported

6 7.5%

Died

2 2.5%

Euthanised

1 1.3%

Not known

63 79%

Problems reported at the same time

28 35%

14 18%

13 16%

12 15%

10 13%

9 11%

8 10%

Skin rash or irritation

7 8.8%

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). Pyrantel treats roundworms and hookworms.

Products with this combination include Heartgard Plus, Tri-Heart Plus, Iverhart Plus. 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 + Pyrantel cause excessive licking and/or grooming in dogs?: 80 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 14 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).

Excessive licking and/or grooming with similar medicines

Excessive licking and/or grooming after Milbemycin Oxime + Spinosad (Trifexis) 88 reports · 0.1% of its reports
Excessive licking and/or grooming after Moxidectin (ProHeart 6) 27 reports · 0.1% of its reports
Excessive licking and/or grooming after Milbemycin Oxime (Interceptor) 30 reports · 0.1% of its reports
Excessive licking and/or grooming after Selamectin (Revolution) 51 reports · 0.2% of its reports

All reported side effects of Ivermectin + Pyrantel in dogs · Medicines most reported with excessive licking and/or grooming