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

371 reports to the FDA describe swelling in dogs given Milbemycin Oxime + Praziquantel. That is 1.2% of all reports for this medicine, compared with 2.8% across reports for all dog medicines, so it is reported less often than average with this medicine.

371Reports

29%Marked serious

45%Recovered

5.7%Died or euthanised

23 daysTypical onset

How soon it started

Same day

79 29%

1–2 days

21 7.7%

3–7 days

12 4.4%

1–4 weeks

34 12%

Over a month

127 47%

How the animals did

Recovered

168 45%

Still unwell when reported

91 25%

Died

10 2.7%

Euthanised

11 3.0%

Not known

91 25%

Problems reported at the same time

111 30%

93 25%

57 15%

49 13%

38 10%

Injection site reaction

30 8.1%

Breathing problems

27 7.3%

Liver problems

26 7.0%

Age of the animals

Under 1 year

1–3 years

127

4–7 years

8–11 years

12+ years

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 swelling in dogs?: 371 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 23 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).

Swelling with similar medicines

Swelling after Ivermectin + Pyrantel (Heartgard Plus) 839 reports · 0.6% of its reports
Swelling after Milbemycin Oxime + Spinosad (Trifexis) 959 reports · 0.7% of its reports
Swelling after Moxidectin (ProHeart 6) 7,913 reports · 16% of its reports
Swelling after Milbemycin Oxime (Interceptor) 257 reports · 0.9% of its reports
Swelling after Selamectin (Revolution) 410 reports · 1.4% of its reports
Swelling after Ivermectin (Heartgard) 204 reports · 1.7% of its reports
Swelling after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 66 reports · 0.8% of its reports
Swelling after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 22 reports · 1.9% of its reports

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