Weakness after Selamectin (Revolution) in dogs

214 reports to the FDA describe weakness in dogs given Selamectin. That is 0.7% of all reports for this medicine, compared with 1.4% across reports for all dog medicines, so it is reported less often than average with this medicine.

214Reports

20%Marked serious

11%Recovered

22%Died or euthanised

1 daysTypical onset

How soon it started

Same day

41 48%

1–2 days

20 24%

3–7 days

6 7.1%

1–4 weeks

10 12%

Over a month

8 9.4%

How the animals did

Recovered

23 11%

Still unwell when reported

34 16%

Died

39 18%

Euthanised

8 3.7%

Not known

110 51%

Problems reported at the same time

100 47%

73 34%

57 27%

51 24%

46 21%

43 20%

37 17%

24 11%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Selamectin prevents heartworm and treats fleas, ear mites and some worms (spot-on).

Products with this ingredient include Revolution. 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 Selamectin cause weakness in dogs?: 214 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 1 day 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).

Weakness with similar medicines

Weakness after Ivermectin + Pyrantel (Heartgard Plus) 453 reports · 0.3% of its reports
Weakness after Milbemycin Oxime + Spinosad (Trifexis) 847 reports · 0.7% of its reports
Weakness after Moxidectin (ProHeart 6) 913 reports · 1.8% of its reports
Weakness after Milbemycin Oxime + Praziquantel (Interceptor Plus) 256 reports · 0.8% of its reports
Weakness after Milbemycin Oxime (Interceptor) 223 reports · 0.7% of its reports
Weakness after Ivermectin (Heartgard) 229 reports · 1.9% of its reports
Weakness after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 76 reports · 0.9% of its reports

All reported side effects of Selamectin in dogs · Medicines most reported with weakness