Urinary incontinence after Ivermectin + Pyrantel (Heartgard Plus) in dogs

190 reports to the FDA describe urinary incontinence in dogs given Ivermectin + Pyrantel. That is 0.1% of all reports for this medicine, compared with 0.6% across reports for all dog medicines, so it is reported less often than average with this medicine.

190Reports

58%Marked serious

31%Recovered

5.8%Died or euthanised

9 daysTypical onset

How soon it started

Same day

29 27%

1–2 days

16 15%

3–7 days

7 6.6%

1–4 weeks

17 16%

Over a month

37 35%

How the animals did

Recovered

57 30%

Recovered with lasting effects

1 0.5%

Still unwell when reported

20 11%

Died

4 2.1%

Euthanised

7 3.7%

Not known

101 53%

Problems reported at the same time

46 24%

40 21%

35 18%

33 17%

22 12%

20 11%

19 10%

17 8.9%

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 urinary incontinence in dogs?: 190 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 9 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).

Urinary incontinence with similar medicines

Urinary incontinence after Milbemycin Oxime + Spinosad (Trifexis) 309 reports · 0.2% of its reports
Urinary incontinence after Moxidectin (ProHeart 6) 171 reports · 0.3% of its reports
Urinary incontinence after Milbemycin Oxime + Praziquantel (Interceptor Plus) 112 reports · 0.4% of its reports
Urinary incontinence after Milbemycin Oxime (Interceptor) 86 reports · 0.3% of its reports
Urinary incontinence after Selamectin (Revolution) 86 reports · 0.3% of its reports
Urinary incontinence after Ivermectin (Heartgard) 46 reports · 0.4% of its reports

All reported side effects of Ivermectin + Pyrantel in dogs · Medicines most reported with urinary incontinence