Selamectin/Sarolaner Topical for Cats

Medically Reviewed by Joshua Conrad, PharmD on October 11, 2024
Written by Kathleen Claussen, DVM
5 min read

Selamectin/sarolaner topical (Revolution Plus, Stronghold Plus) is a combination internal and external antiparasitic medicine for cats and kittens. It is given topically (applied to the skin) at the back of the neck between the shoulder blades once a month (every 30 days). Selamectin is classified as an avermectin antiparasitic, and sarolaner is classified as an isoxazoline ectoparasiticide.  Selamectin/sarolaner topical is approved by the FDA for cats and kittens at least 8 weeks old and weighing at least 2.8 pounds (1.3 kilograms).  

Selamectin/sarolaner topical is approved in cats and kittens for the following:

  • Prevention of heartworm disease
  • Treatment and prevention of flea infestations
  • Treatment and control of ear mite infestations
  • Treatment and control of roundworm and hookworm infestations
  • Prevention of tick infestations (black-legged tick, Gulf Coast tick, and American dog tick)

Selamectin/sarolaner topical can be used “extra-label” or “off-label” for chewing lice. “Extra-label” or “off-label” means that there is evidence of safe and effective use but the FDA has not approved that use.

Selamectin/sarolaner topical is generally well-tolerated in cats and kittens. After fleas and ticks start feeding on the cat, adult fleas will start to die in 6 to 12 hours and ticks will die in 24 to 72 hours.

Selamectin/sarolaner topical is available by prescription from your veterinarian or from a veterinary pharmacy. It is available as a topical liquid in various size doses.

Selamectin/sarolaner is a topical liquid placed at the back of the neck to kill fleas and ticks, prevent heartworm disease, treat ear mites, and treat two types of intestinal parasites. Cats should be at least 8 weeks old to receive selamectin/sarolaner topical.

Give selamectin/sarolaner topical every 30 days (monthly) without stopping for best results.

To apply selamectin/sarolaner topical, make sure the skin at the back of the cat’s neck between the shoulder blades is dry. Using the appropriate tube, part the hair and squeeze the contents of the tube directly onto the skin.  Do not touch that area until it is completely dry. The selamectin/sarolaner will be absorbed into the bloodstream. Avoid bathing your cat within 24 hours of application.  Do not allow your cat or other pets in the household to rub or lick the application site until it dries.

Always follow your veterinarian’s directions for giving medicines to animals. Remember to tell your veterinarian about any medicines, vitamins, supplements, or herbal therapies that you are giving your pet. Talk to your veterinarian before stopping any pet medicines.  

  • Selamectin/sarolaner is FDA-approved for use in cats and kittens.
  • Selamectin/sarolaner is a topical product applied every 30 days.
  • Selamectin/sarolaner is effective against fleas, ticks, heartworm, intestinal parasites, and ear mites.
  • Selamectin/sarolaner starts to kill fleas within the first 6 to 12 hours after application.
  • Selamectin/sarolaner starts to kill ticks within the first 24 to 72 hours after application.

You and your veterinarian should monitor your pet for improvement of their condition, as well as for side effects of the medicine. You should monitor for signs of improvement such as fewer live adult fleas and ticks, less itching, and less scratching. If selamectin/sarolaner is used for ear mites, follow-up ear tests may be done by your veterinarian. If selamectin/sarolaner is used for intestinal parasites, follow-up fecal (stool) tests may be checked. Before giving selamectin/sarolaner for heartworms, your veterinarian may test for heartworm disease if the cat is more than 6 months old.

Do not use selamectin/sarolaner in cats that are allergic to it. Do not use selamectin/sarolaner in cats that are less than 8 weeks old. Use with caution in cats that are in poor body condition (underweight), sick, or frail. Although it appears to be safe to use in breeding, pregnant, or nursing pets, it should still be given with caution in these animals. Use with caution in cats with the MDR1 gene mutation. Do not use selamectin/sarolaner near a flame as it is flammable.

Selamectin/sarolaner is usually well-tolerated in cats. Side effects are rare. They include:

  • Scratching at the neck
  • Slight hair loss at the application site
  • Powdery residue after application has dried
  • Greasiness at the application site
  • Clumping or spiking of the hair
  • Diarrhea or loose stools
  • Vomiting
  • Mild skin reactions, redness, or hives
  • Decreased appetite
  • Tiredness

Most side effects happen if the selamectin/sarolaner is accidentally given by mouth. You might see excessive drooling, increased urination (peeing), vomiting, decreased appetite, or tiredness.

While there is a low risk of serious side effects, this can happen with selamectin/sarolaner.  Signs of this can include seizures, depression, weakness, dilated pupils, or difficulty walking.  

If you think that your cat is having a serious side effect or may have been overdosed, call your veterinary clinic immediately. If it is outside of regular office hours, you may contact a local emergency veterinary hospital or an animal poison control center. 

You can reach the ASPCA Animal Poison Control Center at 888-426-4435 or the Pet Poison Helpline at 855-764-7661.

Using multiple medicines can sometimes change how your pet’s medicines work or increase your pet’s risk for serious side effects. Always tell your veterinarian about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements that your pet is using.

During clinical studies, selamectin/sarolaner was used safely with vaccines, deworming products, sedatives, anesthetics, antibiotics, corticosteroids, and nonsteroidal anti-inflammatory drugs (NSAIDs).

Some medications that may interact with selamectin are spironolactone, “azole” antifungals such as itraconazole or ketoconazole, cyclosporine, diltiazem, and erythromycin.  

This may not be a complete list of medicines that can interact with acepromazine. Always check with your veterinarian.

  • Keep selamectin/sarolaner out of reach of children.
  • Wash your hands after giving selamectin/sarolaner to your pet.
  • Do not handle selamectin/sarolaner if you are allergic to it.
  • Avoid contact of selamectin/sarolaner with eyes, skin, and clothing.
  • Avoid contact with the area of application on your cat until it is dry.

Selamectin/sarolaner is well tolerated by animals and the risk of an overdose is low. If you are concerned your pet is having an adverse reaction or if you suspect your pet has ingested or gotten too much selamectin/sarolaner, call your veterinarian or veterinary emergency clinic immediately.

If your pet misses a dose, give the dose when you remember and then continue with the rest of the medicine at the correct time.  Do not double the dose of the medicine. 

Store selamectin/sarolaner in the original packaging below 86 F (30 C). Protect it from flame, fire, or igniter.