Skin redness after Selamectin (Revolution) in cats

The FDA has received 1,241 reports of skin redness in cats after Selamectin. That is 5.7% of all reports for this medicine, compared with 2.2% across reports for all cat medicines, so it is reported unusually often with this medicine.

1,241Reports

2.6%Marked serious

5.6%Recovered

1.0%Died or euthanised

1 daysTypical onset

How soon it started

Same day

141 29%

1–2 days

210 43%

3–7 days

80 16%

1–4 weeks

39 8.0%

Over a month

19 3.9%

How the animals did

Recovered

68 5.5%

Recovered with lasting effects

1 0.1%

Still unwell when reported

270 22%

Died

10 0.8%

Euthanised

3 0.2%

Not known

889 72%

Problems reported at the same time

Hair loss

1,082 87%

Application site reaction

506 41%

Itching

266 21%

Skin rash or irritation

100 8.1%

68 5.5%

62 5.0%

49 3.9%

40 3.2%

Age of the animals

Under 1 year

128

1–3 years

418

4–7 years

356

8–11 years

189

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 skin redness in cats?: 1,241 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).

Skin redness with similar medicines

Skin redness after Eprinomectin + Esafoxolaner + Praziquantel (NexGard Combo) 45 reports · 1.4% of its reports

All reported side effects of Selamectin in cats · Medicines most reported with skin redness