Nexgard Spectra Large (purple)

What This Medication Is Used For

NexGard Spectra is a prescription chewable tablet for dogs that veterinarians use for parasite control and prevention as part of a broader health plan.

Conditions it treats:
• Flea infestations
• Tick infestations, including common tick species found in Canada
• Prevention of heartworm disease
• Intestinal nematodes, including adult hookworms, roundworms, and whipworms

Typical symptoms before treatment:
• Scratching, biting, or licking from flea irritation
• Ticks found on the skin after outdoor exposure
• Worm signs such as soft stool, diarrhea, or a pot-bellied look in some dogs (your vet will confirm the cause)

When veterinarians commonly prescribe it:
• When your dog needs coverage for external parasites and intestinal worms with one prescription product
• When your veterinarian includes heartworm prevention in your dog’s routine care
• When risk is higher due to travel, boarding, grooming visits, or time outdoors

How It Works

This product contains two active ingredients that work in different ways. One targets external parasites such as fleas and ticks, and the other targets internal parasites, including heartworm prevention and certain intestinal worms. Your veterinarian chooses it when the goal is broad parasite control with a single prescription medication.

How it differs from older or alternative treatments
Some parasite plans use separate products, one for fleas and ticks and another for heartworm and worms. NexGard Spectra combines both categories in one chewable tablet, so your veterinarian can simplify the plan when it fits your dog’s needs.

Why vets use it for ongoing management
Parasite risk changes with season, location, and lifestyle. Your veterinarian may use this product as part of a consistent prevention plan and adjust choices based on testing, travel, and your dog’s health history.

Dosage and Strength Information

Your veterinarian decides the dose and how often to give it based on your dog’s weight, medical history, parasite risk, and any recent test results. Do not change directions on your own.

What this specific strength is generally prescribed for
NexGard Spectra Large (purple) is labelled as 15 mg/75 mg. Veterinarians typically select this size for dogs in the “large” weight range when it matches the prescribed plan. Always confirm the correct size with your vet and weigh your dog when recommended.

Other NexGard Spectra sizes on The Pet Pharmacist:
• XS (orange)
• Small (yellow)
• Medium (green)
• XL (red)

Safety Information and Possible Side Effects

Side effects vary by dog. Reported effects can include digestive upset such as vomiting or diarrhea. Some dogs may seem tired or have a reduced appetite.

Contact your veterinarian if you notice:
• Vomiting or diarrhea that does not settle
• Marked tiredness, appetite changes, or behaviour changes
• Tremors, unsteady movement, or seizures
• Any sudden change that concerns you

Any age, health, or species limitations
NexGard Spectra is indicated for dogs and puppies 8 weeks of age or older. Safety has not been evaluated in breeding, pregnant, or lactating dogs. Isoxazoline-class drugs have been associated with neurologic reactions in some dogs, including dogs without a prior history, so your veterinarian should review seizure history before prescribing.

Prescription Requirements in Canada

A valid veterinary prescription is required by law for prescription medications. Your prescribing veterinarian must be licensed and practising in Canada.

How prescription upload and verification works
• Your veterinarian can call or fax a prescription to the pharmacy
• You can request that the pharmacy contact your veterinarian for authorization
• If you attach a copy to your order, you must mail the original prescription before shipping
Orders are not shipped until prescription authorization is received and verified.

Shipping and Fulfillment Information

Your order cannot be released for shipping until prescription authorization is confirmed.

Secure and discreet packaging
Orders ship in packaging intended to protect your items during transit.

General processing and delivery expectations
• Shipping is within Canada only, using Canada Post, with service options selected at checkout
• Orders ship with tracking
• Prescription orders require proof of delivery and may be carded for pickup at your local post office, with ID required
• Shipping time is counted from when the package leaves the pharmacy
• Once authorization and stock are in place, the pharmacy aims to ship the same business day, and special-order items may take several weekdays before they are ready to ship

Note: Pricing on the product page is listed per chewable tablet, and a dispensing fee applies.

Frequently Asked Questions

1. Can I buy NexGard Spectra Large (purple) without a prescription?
   No. The pharmacy must have valid authorization from a licensed Canadian veterinarian before dispensing and shipping.

2. Can my vet send the prescription directly to The Pet Pharmacist?
   Yes. Your veterinarian can call or fax the prescription, or you can ask the pharmacy to request authorization on your behalf.

3. Do I need heartworm testing before starting?
   Your veterinarian may recommend testing based on your dog’s history and risk. Follow your veterinarian’s guidance before starting prevention products.

4. Can my dog take this if they have had seizures before?
   Tell your veterinarian. Isoxazoline-class drugs have been associated with neurologic reactions, and your vet will weigh risks and alternatives.

5. What should I do if my dog vomits after a dose?
   Contact your veterinarian for advice, especially if vomiting continues, your dog seems unwell, or other symptoms appear.