Diarrhea after Milbemycin Oxime + Praziquantel (Interceptor Plus) in dogs

2,695 reports to the FDA describe diarrhea in dogs given Milbemycin Oxime + Praziquantel. That is 8.5% of all reports for this medicine, compared with 8.4% across reports for all dog medicines.

2,695Reports

15%Marked serious

36%Recovered

2.9%Died or euthanised

5 daysTypical onset

How soon it started

Same day

630 30%

1–2 days

356 17%

3–7 days

117 5.5%

1–4 weeks

212 10%

Over a month

799 38%

How the animals did

Recovered

959 36%

Recovered with lasting effects

5 0.2%

Still unwell when reported

785 29%

Died

42 1.6%

Euthanised

35 1.3%

Not known

869 32%

Problems reported at the same time

1,210 45%

539 20%

482 18%

381 14%

Didn't work as expected

160 5.9%

Liver problems

107 4.0%

Didn't prevent heartworm

101 3.7%

Behaviour change

96 3.6%

Age of the animals

Under 1 year

592

1–3 years

840

4–7 years

550

8–11 years

398

12+ years

230

About this medicine

Milbemycin Oxime prevents heartworm and controls some intestinal worms (monthly). Praziquantel treats tapeworms.

Products with this combination include Interceptor 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 Milbemycin Oxime + Praziquantel cause diarrhea in dogs?: 2,695 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 5 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).

Diarrhea with similar medicines

Diarrhea after Ivermectin + Pyrantel (Heartgard Plus) 9,076 reports · 6.1% of its reports
Diarrhea after Milbemycin Oxime + Spinosad (Trifexis) 7,183 reports · 5.5% of its reports
Diarrhea after Moxidectin (ProHeart 6) 4,291 reports · 8.5% of its reports
Diarrhea after Milbemycin Oxime (Interceptor) 2,873 reports · 9.7% of its reports
Diarrhea after Selamectin (Revolution) 1,974 reports · 6.7% of its reports
Diarrhea after Ivermectin (Heartgard) 693 reports · 5.8% of its reports
Diarrhea after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 954 reports · 11% of its reports
Diarrhea after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 125 reports · 11% of its reports

All reported side effects of Milbemycin Oxime + Praziquantel in dogs · Medicines most reported with diarrhea