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April 20, 2026
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Simparica Trio Chewable Tablets for Dogs
From Price range: £26.53 through £382.29
- Prescription Required
Simparica Trio Chewable Tablets for Dogs
From Price range: £26.53 through £382.29
One chew. Once a month. Complete protection.
Simparica Trio is the only monthly flea, tick and worm treatment for dogs that combines three active ingredients in a single chewable dose. It protects your dog from:
- Fleas: Killed before they can lay eggs
- Ticks: Targets 4 major species with immediate and persistent activity
- Heartworm and Lungworm: Monthly prevention and treatment
- Roundworms and Hookworms: Treated in the same oral dose
As a bonus, rapid flea elimination also reduces the risk of flea tapeworm (Dipylidium caninum) infestations.
Order Monday to Friday before 14:00pm to guarantee next
day delivery.
Please select size and quantity as shown in your prescription.
Ordering Prescription-Only Products
This item requires a current prescription from your vet before we can dispatch it. The good news? Sorting it out is simple and only takes a moment.
- Select or register your pet
- Attach a clear image or PDF of the prescription
- Complete your order at checkout
As soon as your prescription reaches us, our team will verify the details and get your pet’s treatment posted out to you.
Order Monday to Friday before 14:00pm to guarantee next
day delivery.
Product Features
One chew. Once a month. Complete protection.
Simparica Trio is the only monthly flea, tick and worm treatment for dogs that combines three active ingredients in a single chewable dose. It protects your dog from:
- Fleas: Killed before they can lay eggs
- Ticks: Targets 4 major species with immediate and persistent activity
- Heartworm and Lungworm: Monthly prevention and treatment
- Roundworms and Hookworms: Treated in the same oral dose
As a bonus, rapid flea elimination also reduces the risk of flea tapeworm (Dipylidium caninum) infestations.
Product Details
This product cannot be dispatched without a valid written prescription from a registered veterinary surgeon.
Simparica Trio Chewable Tablets for Dogs are a broad-spectrum monthly parasite treatment combining three active ingredients — sarolaner, moxidectin, and pyrantel embonate — in a single palatable tablet. This precise formulation delivers an all-in-one internal and external parasite routine in a single chew.
One tablet simultaneously covers external parasites (fleas, ticks, and mites) and internal parasites (roundworms, hookworms, lungworm, and heartworm). For dog owners managing multiple parasite risks, that means fewer products, simpler routines, and no missed doses.
Simparica Trio is prescribed for dogs suffering from, or at risk from, mixed external and internal parasitic infestations. It is indicated when treatment against ticks, fleas or mites and gastrointestinal worms is needed at the same time. If your dog only requires flea and tick protection without intestinal worm or lungworm coverage, standard Simparica is typically prescribed instead. The tablets are reddish-brown, highly palatable, and easy to give by hand or mixed into food. Do not divide or split the tablets.
Simparica Trio Ingredients: Sarolaner, Moxidectin, Pyrantel Embonate
Legal Category: AVM-GSL
View the Summary of Product Characteristics (SPC) information for this product
Instructions
Administer one chewable tablet by mouth once a month, ideally on the same date. Any repeat doses must follow a minimum one-month interval.
The tablet can be offered directly by hand as a treat or hidden inside a small portion of food. Ensure the dog swallows the entire tablet to guarantee a full dose.
If a monthly dose is missed, administer the tablet as soon as you remember, and reset your regular monthly schedule from that specific date forward.
Never double up or administer two tablets at once to compensate for a missed dose.
Wash your hands after handling the product, and return the blister pack to the carton after use, storing it out of the sight and reach of children.
Warnings & Contraindications
Do not use in cases of known hypersensitivity to sarolaner, moxidectin, pyrantel, or any of the product’s inactive excipients.
Use in puppies under 8 weeks of age, or in dogs weighing less than 1.25 kg, is not recommended unless your vet has carried out a specific benefit-risk assessment.
Not recommended for use during pregnancy, lactation, or in dogs intended for breeding, as safety during these stages has not been clinically established.
Use with caution in dogs with a known MDR1 (multidrug-resistance protein 1) gene deficiency, such as Collies and related herding breeds. The recommended weight-based dose must be strictly observed in these animals.
Tell your vet about any other medicines your dog is taking. Certain medicines that inhibit p-glycoprotein (such as cyclosporine, ketoconazole, spinosad, or verapamil) should only be used alongside Simparica Trio if your vet judges the benefit outweighs the risk.
Simparica Trio prevents heartworm disease but is not effective against adult heartworms (Dirofilaria immitis). Dogs living in, or returning from, heartworm-endemic areas should be tested by a vet before starting preventative treatment — only dogs that test negative should be treated.
This medicine is exclusively formulated for dogs. Do not administer to cats or any other animal species.
Sizes
Simparica Trio Chewable Tablet Sizes & Dog Weight Ranges
Simparica Trio sizes are matched to six weight ranges, each meticulously aligned to a specific canine body weight. Your vet will confirm the exact tablet strength required on your prescription. The table below is for customer reference:
| Dog Weight Class | Chewable Tablet Strength (Sarolaner / Moxidectin / Pyrantel) | Available Pack Sizes |
| 1.25 kg – 2.5 kg | 3 mg / 0.06 mg / 12.5 mg | Pack of 3 or 6 |
| >2.5 kg – 5 kg | 6 mg / 0.12 mg / 25 mg | Pack of 3 or 6 |
| >5 kg – 10 kg | 12 mg / 0.24 mg / 50 mg | Pack of 3 or 6 and 10 x pack of 3 |
| >10 kg – 20 kg | 24 mg / 0.48 mg / 100 mg | Pack of 3 or 6 and 10 x pack of 3 |
| >20 kg – 40 kg | 48 mg / 0.96 mg / 200 mg | Pack of 3 or 6 and 10 x pack of 3 |
| >40 kg – 60 kg | 72 mg / 1.44 mg / 300 mg | Pack of 3 or 6 |
Note: For dogs weighing over 60 kg, an appropriate combination of tablet strengths must be used under strict veterinary direction. To ensure correct dosing, your dog’s body weight should be determined as accurately as possible.
Key Benefits
- Kills fleas within 8 hours and prevents re-infestation for up to 5 weeks
- Kills 4 species of ticks with immediate and persistent activity
- Prevents heartworm disease (Dirofilaria immitis)
- Prevents and treats lungworm (Angiostrongylus vasorum)
- Treats roundworms and hookworms
- Treats sarcoptic mange and demodicosis (Demodex canis), and prevents eyeworm (Thelazia callipaeda) infection
- Highly palatable, once-monthly chewable tablet that can be given with or without food
- Safe to use in puppies and dogs from 8 weeks of age and weighing at least 1.25 kg
- Classified as a POM-V medicine — a valid veterinary prescription is required to order
Ingredients
Active Ingredient
Moxidectin, Pyrantel Embonate, Sarolaner
How it works to order pet prescription medications online
Prescription required for this item. We need a valid written prescription from your vet before we can dispatch.
Legal category: POM-V
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Frequently asked questions
Simparica Trio Side Effects
Simparica Trio possesses a strong safety profile, and side effects are usually rare. In extensive clinical registration studies, adverse reactions in dogs were classified as very rare, affecting fewer than 1 in 10,000 treated dogs.
Very rare, usually mild and transient signs may include gastrointestinal signs (such as vomiting or diarrhoea), systemic signs (such as lethargy or loss of appetite), or neurological signs (such as tremor, ataxia, or convulsions). If any of these signs persist or concern you, contact your veterinarian immediately.[Sources]
What is Simparica Trio for dogs used for?
Simparica Trio is used for treating flea and tick infestations, sarcoptic mange, and demodicosis. It simultaneously prevents heartworm disease, prevents and treats lungworm (Angiostrongylus vasorum), treats roundworms and hookworms, prevents eyeworm infection, and reduces the overall transmission risk of flea tapeworms.
How does Simparica Trio work?
Its three active ingredients work together through your dog's bloodstream. Sarolaner targets fleas, ticks, and mites when they bite and feed; moxidectin prevents heartworm and treats lungworm; and pyrantel embonate clears intestinal roundworms and hookworms — all from a single monthly chew.
What is the difference between Simparica and Simparica Trio?
Standard Simparica contains only sarolaner, focusing exclusively on external parasites like fleas, ticks, and mites. Simparica Trio adds moxidectin and pyrantel embonate to the chew, expanding the protection spectrum to include life-threatening internal parasites like lungworm, heartworm, and common intestinal roundworms.
Is Simparica Trio safe for dogs?
Yes. Simparica Trio is rigorously tested and fully licensed for use across the UK. Side effects are officially classified as very rare, occurring in fewer than 1 in 10,000 treated dogs. Exercise proper caution and strict dosing adherence with herding breeds carrying the MDR1 gene variant.
How long does Simparica Trio last?
Each chew provides a full month of protection. It begins killing fleas already on your dog within 8 hours of dosing, and its persistent activity against fleas continues for up to 5 weeks, so your dog stays covered right through to the next monthly dose.
How often do you give Simparica Trio?
It is given exactly once a month. To keep protection seamless, try to administer the chewable on the same calendar day each month.
Can puppies take Simparica Trio?
Yes — puppies can start taking Simparica Trio from 8 weeks of age, provided they have reached the minimum required body weight threshold of 1.25 kg.
Can cats take Simparica Trio?
No. Simparica Trio is exclusively formulated and licensed for dogs. It must never be given to cats or any other species — speak to your vet about suitable parasite treatments licensed for cats.
How much does Simparica Trio cost?
Pricing is based on the specific tablet strength and whether you purchase a 3-pack or a 6-pack box. Select your dog's correct weight band from the product menu to view current authorised pharmacy pricing.
Does Simparica Trio prevent lungworm in dogs?
Yes. Simparica Trio is one of the few oral monthly chews licensed to both prevent and treat lungworm (Angiostrongylus vasorum) infections in dogs, making it highly effective for dogs that scavenge outdoors near slugs and snails.
Does Simparica Trio prevent heartworm in dogs?
Yes, it prevents heartworm disease by targeting heartworm larvae. However, it is not effective against pre-existing adult heartworm infections. If your dog lives in, or has travelled to, a heartworm-endemic area, your vet should test them before starting the monthly schedule — only dogs that test negative should begin treatment.
Can I buy Simparica Trio for dogs without a prescription?
No. Simparica Trio is classified as a POM-V medicine in the UK. By law, it can only be dispensed after a registered veterinary surgeon has examined your dog and issued a valid written prescription. You can upload a scan or digital photo of this document directly during the checkout process.
How many types of ticks does Simparica Trio kill?
It kills 4 tick species common to Europe and the UK — Ixodes ricinus (the sheep tick, the main vector for Lyme disease), Ixodes hexagonus, Rhipicephalus sanguineus, and Dermacentor reticulatus. Persistent killing activity lasts up to 5 weeks for the first three species and 4 weeks for Dermacentor reticulatus.
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