Itching after Selamectin (Revolution) in dogs

The FDA has received 2,024 reports of itching in dogs after Selamectin. That is 6.9% of all reports for this medicine, compared with 4.3% across reports for all dog medicines, so it is reported unusually often with this medicine.

2,024Reports

5.2%Marked serious

5.8%Recovered

1.0%Died or euthanised

Same dayTypical onset

How soon it started

Same day

302 50%

1–2 days

123 20%

3–7 days

48 8.0%

1–4 weeks

61 10%

Over a month

67 11%

How the animals did

Recovered

114 5.6%

Recovered with lasting effects

3 0.1%

Still unwell when reported

239 12%

Died

16 0.8%

Euthanised

5 0.2%

Not known

1,647 81%

Problems reported at the same time

Skin rash or irritation

291 14%

Hair loss

267 13%

Didn't stop fleas

197 9.7%

Application site reaction

182 9.0%

170 8.4%

164 8.1%

140 6.9%

129 6.4%

Age of the animals

Under 1 year

378

1–3 years

646

4–7 years

500

8–11 years

268

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 itching in dogs?: 2,024 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 the same 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).

Itching with similar medicines

Itching after Ivermectin + Pyrantel (Heartgard Plus) 2,733 reports · 1.9% of its reports
Itching after Milbemycin Oxime + Spinosad (Trifexis) 6,069 reports · 4.7% of its reports
Itching after Moxidectin (ProHeart 6) 2,435 reports · 4.8% of its reports
Itching after Milbemycin Oxime + Praziquantel (Interceptor Plus) 763 reports · 2.4% of its reports
Itching after Milbemycin Oxime (Interceptor) 563 reports · 1.9% of its reports
Itching after Ivermectin (Heartgard) 528 reports · 4.4% of its reports
Itching after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 93 reports · 1.1% of its reports
Itching after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 57 reports · 4.9% of its reports

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