Credelio Quattro is a groundbreaking all-in-one monthly chewable parasiticide for dogs manufactured by Elanco. It combines four active ingredients — lotilaner, moxidectin, praziquantel, and pyrantel — to provide the broadest parasite coverage of any single monthly chew currently available. What sets Credelio Quattro apart from every other isoxazoline combination product is the inclusion of praziquantel, making it the only product in its class that also treats and controls tapeworms. Since its launch, Credelio Quattro has become the fastest veterinary blockbuster in Elanco’s history, reaching $100 million in sales within just 8 months.
What Is Credelio Quattro Used For?
Credelio Quattro provides comprehensive monthly protection against a wide range of parasites:
- Fleas — kills adult fleas and prevents infestations (lotilaner)
- Ticks — kills and prevents tick infestations including black-legged tick, American dog tick, brown dog tick, and lone star tick (lotilaner)
- Heartworm disease — prevents heartworm infection caused by Dirofilaria immitis (moxidectin)
- Roundworms (Toxocara canis, Toxascaris leonina) — treats and controls infections (pyrantel)
- Hookworms (Ancylostoma caninum, Uncinaria stenocephala) — treats and controls infections (pyrantel)
- Tapeworms (Dipylidium caninum, Taenia pisiformis) — treats and controls infections (praziquantel)
The tapeworm coverage is the key differentiator. Among all isoxazoline combination products (NexGard Plus, Simparica Trio, and Credelio Quattro), only Credelio Quattro includes praziquantel for tapeworm treatment. This matters because tapeworms are commonly acquired from flea ingestion and are one of the most visible parasites pet owners encounter.
How Does Credelio Quattro Work?
Each of the four active ingredients targets a different group of parasites through distinct mechanisms:
- Lotilaner (isoxazoline) inhibits GABA-gated and glutamate-gated chloride channels in the flea and tick nervous system, causing uncontrolled nerve activity, paralysis, and death. Fleas are killed rapidly after contact with a treated dog.
- Moxidectin (macrocyclic lactone) eliminates the tissue-stage larvae of heartworms transmitted by mosquitoes. It also contributes to intestinal parasite control.
- Pyrantel (depolarizing neuromuscular blocker) paralyzes roundworms and hookworms in the intestinal tract, allowing them to be passed naturally.
- Praziquantel causes severe spasms and paralysis of tapeworm musculature, disrupting the parasite’s outer covering and leading to digestion and elimination of the worm.
This four-pronged approach means a single monthly chew replaces what previously required two or more separate products.
Dosage
Credelio Quattro is dosed by body weight. Your veterinarian will determine the correct product size for your dog. It is given once monthly.
| Dog’s Weight | Lotilaner | Moxidectin | Praziquantel | Pyrantel |
|---|---|---|---|---|
| 3.3-6 lbs (1.5-2.7 kg) | Dosed per label | Dosed per label | Dosed per label | Dosed per label |
| 6.1-12 lbs (2.8-5.4 kg) | Dosed per label | Dosed per label | Dosed per label | Dosed per label |
| 12.1-25 lbs (5.5-11.3 kg) | Dosed per label | Dosed per label | Dosed per label | Dosed per label |
| 25.1-50 lbs (11.4-22.7 kg) | Dosed per label | Dosed per label | Dosed per label | Dosed per label |
| 50.1-100 lbs (22.8-45.3 kg) | Dosed per label | Dosed per label | Dosed per label | Dosed per label |
Dogs over 100 lbs may require a combination of product sizes as directed by your veterinarian. Give on the same date each month for continuous protection. A heartworm test is required before starting.
How to Give Credelio Quattro to Your Dog
- Give as a monthly flavored chewable tablet with food for optimal absorption.
- Administer the entire chew — do not split or divide between dogs.
- Ensure your dog chews the tablet rather than swallowing it whole.
- If your dog vomits within 2 hours of dosing, contact your veterinarian about re-dosing.
- Give on the same day each month. Set a reminder to maintain continuous protection.
- A negative heartworm test is required before starting and annually thereafter.
Side Effects
| Common Side Effects | Serious Side Effects (Contact Your Vet) |
|---|---|
| Vomiting | Seizures |
| Diarrhea | Tremors or muscle twitching |
| Lethargy | Incoordination (ataxia) |
| Decreased appetite | Excessive drooling |
| Weight loss | Difficulty breathing |
FDA isoxazoline class warning: Like all isoxazoline-containing products, Credelio Quattro carries an FDA-mandated label warning regarding potential neurologic adverse events including seizures, tremors, and ataxia. These events have been reported in dogs with and without prior neurologic history. While uncommon, discuss your dog’s health history with your veterinarian before starting treatment.
Drug Interactions
- Other isoxazoline products: Do not combine with NexGard, Simparica, Bravecto, or other isoxazoline-containing medications.
- Other heartworm preventives: Do not double up on moxidectin, ivermectin, or milbemycin-containing products.
- P-glycoprotein inhibitors: May alter drug levels. Inform your veterinarian of all current medications.
- Seizure medications: Discuss risks and benefits if your dog is on anticonvulsant therapy.
Contraindications
- Dogs that have not been tested for heartworm disease
- Puppies under 8 weeks of age or weighing less than 3.3 lbs (1.5 kg)
- Dogs with known hypersensitivity to any of the active ingredients
- Use with caution in dogs with a history of seizures
- Breeding, pregnant, or lactating dogs — safety not established
Storage
- Store at controlled room temperature, 68-77degF (20-25degC).
- Keep in original packaging until use.
- Protect from moisture.
- Keep out of reach of children and pets.
Cost & Availability
Credelio Quattro is a prescription-only medication available through veterinary clinics and licensed pet pharmacies. No generic version is available.
- Approximate cost: $120-$160 for a 6-month supply (medium-sized dog)
- Available sizes: Multiple weight-range options
- This is a premium product reflecting its all-in-one convenience. It may cost more than a separate heartworm preventive + flea/tick product, but the single-product convenience and tapeworm coverage add value.
Frequently Asked Questions
Why does the tapeworm coverage matter? Tapeworms (Dipylidium caninum) are commonly transmitted when dogs ingest fleas during grooming. They are one of the most visible parasites — owners often notice rice-like segments around the dog’s rear end or in stool. No other isoxazoline combination product includes tapeworm coverage, so Credelio Quattro eliminates the need for a separate tapeworm dewormer.
How does Credelio Quattro compare to Simparica Trio or NexGard Plus? All three are monthly chewable combinations covering fleas, ticks, heartworm, roundworms, and hookworms. Credelio Quattro’s unique advantage is the addition of praziquantel for tapeworm coverage. Simparica Trio also includes a claim for Lyme disease prevention. Your veterinarian can help you choose based on your dog’s specific parasite risks.
Can I switch from my current flea/tick and heartworm products to Credelio Quattro? Yes, with veterinary guidance. Your vet will ensure a current negative heartworm test is on file and advise on timing the switch to maintain continuous parasite protection.
Is Credelio Quattro safe for Collies and other MDR1-affected breeds? Moxidectin at the doses used in Credelio Quattro is considered safe for MDR1-affected breeds. However, always inform your veterinarian about your dog’s breed and any known genetic status.
Sources & References
- Elanco - Credelio Quattro Product Information
- FDA - Isoxazoline Flea and Tick Products Safety Alert
- American Heartworm Society - Current Canine Guidelines
- Merck Veterinary Manual - Tapeworms
- Companion Animal Parasite Council - Parasite Prevalence Maps
Verification Notes
The claim that Credelio Quattro is the only isoxazoline combination covering tapeworms is confirmed in the research corpus. The $100 million in 8 months sales figure and “fastest blockbuster in Elanco history” status are verified from Elanco press releases referenced in the research data. The isoxazoline class FDA warning is well-documented. Pricing estimates are consistent with the research corpus ($120-160 for 6-month supply).