Stronghold For Cats 5.1-15 lbs (2.6-7.5 kg)

Description

Stronghold for Cats 5.1–15 lbs (2.6–7.5 kg) is a selamectin-based spot-on solution from Zoetis, delivering 45 mg selamectin per 0.75 ml tube. Selamectin belongs to the avermectin class of macrocyclic lactones and acts by disrupting chloride channel conductance in invertebrate parasites, producing paralysis and death across multiple parasite types. This variant is formulated exclusively for cats from 6 weeks of age weighing between 2.6 and 7.5 kg, providing monthly flea and heartworm prevention alongside single-dose treatment for ear mites, roundworms, hookworms, and biting lice through one topical application.

Recommended for:

Cats weigh 5.1–15 lbs (2.6–7.5 kg) from 6 weeks of age.

Indication/Coverage

For cats suffering from, or at risk from, mixed parasitic infections, Stronghold 45 mg addresses the following conditions:

• Flea treatment and prevention (Ctenocephalides spp.): Selamectin kills adult fleas on the cat, prevents viable egg production, and eliminates larvae in the environment; ovicidal activity persists for 3 weeks post-application, interrupting the flea reproductive cycle at every stage.
• Heartworm prevention (Dirofilaria immitis, L3/L4 larvae): Monthly application eliminates susceptible larval stages acquired up to one month before dosing; this product does not act against established adult heartworms.
• Ear mite treatment (Otodectes cynotis, adults): A single dose is sufficient for ear mite infestations; do not apply the solution directly into the ear canal.
• Roundworm treatment (Toxocara cati, adults): A single dose clears adult roundworm burden from the intestinal tract.
• Hookworm treatment (Ancylostoma tubaeforme, adults): A single dose treats adult intestinal hookworm infections in cats.
• Biting lice treatment (Felicola subrostratus): A single topical dose eliminates biting lice infestations in cats.

Key Benefits

The following characteristics reflect label-confirmed properties of Stronghold 45 mg for cats in the 2.6–7.5 kg weight range.

• Cat-specific formulation: This variant is labeled for cats only, with the 45 mg selamectin dose calibrated to a minimum of 6 mg/kg across the 2.6–7.5 kg weight range.
• Six-indication coverage: One monthly application addresses fleas, heartworm larvae, ear mites, roundworms, hookworms, and biting lice, reducing the number of separate treatment products required.
• Full flea life cycle disruption: Selamectin kills adult fleas on the animal, renders eggs non-viable, and eliminates environmental larvae via debris shed from the treated cat, targeting reproductive stages beyond what adulticidal-only products achieve.
• Systemic absorption from topical application: Following skin application, selamectin is absorbed transdermally and reaches maximum plasma concentration within approximately 1 day in cats, providing internal parasite coverage without oral dosing.
• 30-day protection interval: Plasma concentrations of selamectin remain detectable at 30 days post-application, supported by a terminal elimination half-life of 8 days in cats, sustaining flea and heartworm larval protection across the full monthly interval.
• Bathing tolerance: Efficacy is maintained when the cat is bathed or exposed to water 2 or more hours after application, per Stronghold label direction.
• Breeding and lactating safety: Zoetis administered Stronghold at 3 times the recommended dose to pregnant and lactating females without adverse effects, making it appropriate for breeding cats within this weight category.
• Established safety margin: Zoetis safety data confirm no adverse effects at 10 times the recommended dose, with field testing conducted across 16 pure cat breeds.

Caution

Hazards to Humans

This product is highly flammable; keep it away from heat, open flame, and sparks during handling. Do not smoke, eat, or drink while applying. Wash hands thoroughly with soap and water immediately after use. Flush any skin or eye contact with water at once; seek medical attention if eye exposure occurs. Keep children away from treated cats for at least 30 minutes or until the coat is fully dry.

Hazards to Domestic Animals

Stronghold 45 mg is for external use in cats only; do not administer orally or by injection. This variant is not for use in animals under 6 weeks of age. Cats suffering from concurrent illness, debilitation, or being underweight for age and size should not receive this product without prior veterinary assessment. Reversible neurological signs, including seizures, have been reported on rare occasions with macrocyclic lactone-class products. No interactions with routinely used veterinary medications or surgical procedures were identified in extensive field trials.

Possible Side Effects

Monitor your cat after each application, particularly following the first dose.

Dermal reactions at the application site occur on rare occasions and may include transient hair loss or mild focal irritation; these effects are generally self-resolving. Temporary hair clumping or a small amount of white powder at the application site may appear within the first 24 hours, which is a documented product characteristic that does not affect efficacy or safety and typically resolves without intervention.

If the cat licks the application site before the coat dries, a brief episode of hypersalivation may rarely occur, attributed to the excipient formulation rather than systemic selamectin toxicity. Keep the cat away from other animals until the treated area is fully dry to prevent this via mutual grooming.

Systemic signs are exceptional. As a macrocyclic lactone, selamectin carries a very low but documented risk of reversible neurological signs including seizures. If neurological changes, persistent behavioral abnormalities, or any unexpected systemic signs appear after dosing, discontinue use and consult a veterinarian promptly.