Is Revolution Plus Safe for Cats? Everything You Should Know First

Revolution Plus is a prescription topical treatment for cats, combining two active ingredients: selamectin and sarolaner. It’s approved for cats and kittens 8 weeks of age or older, weighing 2.8 lbs (≈1.27 kg) or more.

Selamectin is an avermectin-class macrocyclic lactone, while sarolaner belongs to the isoxazoline class of insecticides. Together, they provide broad-spectrum parasite control—targeting fleas, ticks, ear mites, hookworms, roundworms, and heartworm disease, and indirectly helping prevent flea-transmitted tapeworms (Dipylidium caninum).

How It Works

• Selamectin: Paralyzes and kills parasites by interfering with their nerve and muscle function. It penetrates the skin and circulates systemically.
• Sarolaner: Disrupts parasite chloride channels (GABA and glutamate-gated), causing paralysis and death. Although highly selective for parasites, caution is warranted for cats with neurological disorders.

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Parasite Coverage and Benefits

Revolution Plus provides once-monthly, broad-spectrum parasite protection, including:

• Adult fleas and larvae
• Flea-transmitted tapeworms
• Four tick species (American dog tick, Lone Star tick, Gulf Coast tick, and Black-legged tick)
• Ear mites
• Roundworms and hookworms
• Heartworm prevention

Since fleas and ticks can enter homes via clothing or other pets, many veterinarians recommend year-round use even for indoor cats.

Is Revolution Plus Safe for Cats?

Licensed Indications and Restrictions

Revolution Plus is approved for:

• Cats 8 weeks or older
• Weight ≥ 2.8 lbs

Safety has not been established for kittens younger than 8 weeks, or in breeding, pregnant, or lactating cats. Dosage varies by weight group (2.8–5.5 lbs; 5.6–11 lbs; 11.1–22 lbs).

Safety Studies and Adverse Effects

In field safety trials with over 400 cats, reported side effects were generally mild:

• Lethargy (~4%)
• Loss of appetite (~3%)
• Vomiting or diarrhea in some cases

The FDA advises caution in cats with a history of neurological disorders (e.g., seizures) due to the sarolaner component. While reactions are rare, they can include tremors, incoordination, or seizures.

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Known Side Effects

• Temporary hair clumping or mild irritation at the application site
• Lethargy or appetite loss
• Mild vomiting or diarrhea
• Sneezing or eye irritation in sensitive cats

Neurologic Risks (Isoxazoline Class)

Because sarolaner belongs to the isoxazoline class, rare neurological events have been documented. Most cats tolerate Revolution Plus safely when used according to label directions.

Contraindications and Cautions

• Do not use in kittens under 8 weeks or weighing less than 2.8 lbs
• Avoid in pregnant or nursing cats (not yet tested)
• Cats with known neurological issues should be treated under veterinary supervision
• Never use dog formulations on cats

Safety Summary

Revolution Plus is considered safe and effective when used as directed for cats 8 weeks and older, over 2.8 lbs. Most cats experience no side effects or only mild, temporary reactions.

Expert Opinion

Dr. Sarah Hamer, DVM, PhD, DACVM (Veterinary Parasitology, Texas A&M University) notes: “When applied correctly and at labeled doses, topical preventives like Revolution Plus have an excellent safety record in cats. However, veterinarians should always tailor parasite protection plans to each cat’s health status and environment to ensure maximum safety and efficacy.”

Application, Dosing, and Prevention Strategy

Dosage Frequency: Apply once every 30 days

Application Site: Part the fur at the back of the neck, apply to the skin, and avoid contact until dry

Bathing: Wait at least 24 hours before bathing

Weight-Based Tubes

• 2.8–5.5 lbs – Gold cap
• 5.6–11 lbs – Orange cap
• 11.1–22 lbs – Green cap
• For cats over 22 lbs, consult your veterinarian

Parasite Control Strategy

• Routine vet checkups and fecal testing
• Regular vacuuming and washing bedding
• Checking for ticks after outdoor exposure
• Monthly dosing consistency

Cats with chronic or neurological conditions may require an alternative preventive.

Signs of Effectiveness or Problems

Indications It’s Working

• Reduced scratching and no visible fleas/ticks
• Healthier skin and coat
• No signs of ear mites or intestinal worms

Possible Side Effects

• Persistent vomiting, diarrhea, or appetite loss
• Lethargy or unsteady walking
• Hair loss or irritation at the application site

If any occur, contact your veterinarian promptly.

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Why Parasite Prevention Matters

Even indoor cats can get fleas, ticks, or heartworms. Parasites can cause:

• Skin infections and flea allergy dermatitis
• Ear mite infestations
• Intestinal worms can cause weight loss or vomiting
• Heartworm-associated respiratory disease (HARD)

Using a comprehensive preventive like Revolution Plus helps protect cats from these health issues.

Is Revolution Plus the Best Option for Your Cat?

It depends on your cat’s:

• Health history
• Lifestyle (indoor/outdoor)
• Regional parasite risks
• Existing conditions

Your veterinarian can determine if Revolution Plus is the right fit or recommend an alternative.

Conclusion

When applied correctly and under veterinary supervision, Revolution Plus is safe and effective for most cats. It provides broad-spectrum protection against fleas, ticks, worms, mites, and heartworm disease. Rare neurological reactions are minimal compared to the benefits of consistent parasite prevention.

Always follow label instructions and consult your veterinarian to tailor the best parasite prevention plan for your cat.

Explore more in-depth cat care guides and breed insights on I Am Pet Lovers to ensure the perfect match for your home.

Frequently Asked Questions (FAQ)