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Zenrelia for Dogs (Ilunocitinib Tablets)
From Price range: £21.70 through £115.46
- Prescription Required
Zenrelia for Dogs (Ilunocitinib Tablets)
From Price range: £21.70 through £115.46
Zenrelia is a once-daily prescription tablet for dogs aged 12 months and over. It contains ilunocitinib and is licensed to treat itching linked to allergic dermatitis, as well as the clinical signs of atopic dermatitis.
- Active ingredient: ilunocitinib
- Strengths: 4.8mg, 6.4mg, 8.5mg and 15mg
- Given once a day, with or without food
- Scored tablets that split into equal halves
- POM-V, a vet prescription is required
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
Zenrelia is a once-daily prescription tablet for dogs aged 12 months and over. It contains ilunocitinib and is licensed to treat itching linked to allergic dermatitis, as well as the clinical signs of atopic dermatitis.
- Active ingredient: ilunocitinib
- Strengths: 4.8mg, 6.4mg, 8.5mg and 15mg
- Given once a day, with or without food
- Scored tablets that split into equal halves
- POM-V, a vet prescription is required
Product Details
⚠️ This product will be dispatched once a valid prescription is provided and verified by our licensed veterinarian.
What Zenrelia is
Elanco makes Zenrelia film-coated tablets, which contain ilunocitinib, a medicine known as a JAK inhibitor. JAK (Janus kinase) enzymes help pass on the chemical signals behind itching and inflammation in the skin. Ilunocitinib blocks a range of these enzymes, which reduces those signals.
It’s licensed in the UK for two uses in dogs: itching caused by allergic dermatitis, and the clinical signs of atopic dermatitis. Apoquel belongs to the same group of medicines but contains a different active ingredient, oclacitinib.
Zenrelia strengths
Each strength is a yellow, oblong tablet with a score line on both sides. Your vet picks the strength and how many tablets or half tablets to give, based on your dog’s weight.
Zenrelia 4.8mg
Contains 4.8mg of ilunocitinib per tablet, the lowest strength in the range.
Zenrelia 6.4mg
Each 6.4mg tablet contains 6.4mg of ilunocitinib. Available in packs of 30 and 90.
Zenrelia 8.5mg
An 8.5mg ilunocitinib tablet, which can be split along the score line if your vet prescribes half doses.
Zenrelia 15mg
The highest strength, with 15mg of ilunocitinib per tablet. Order a pack of 30 or 90.
Giving Zenrelia
Give Zenrelia once a day, exactly as your vet has prescribed. You can give it with or without food, but try to keep it consistent, as food increases absorption.
If your vet prescribes half a tablet, keep the remaining half in its blister. Use it within 20 days or throw it away.
Before your dog starts Zenrelia
Zenrelia must not be used in dogs that:
- show signs of a weakened immune system
- have a cancer that is getting worse
- are allergic to ilunocitinib or any other ingredient in the tablet
It isn’t recommended for dogs under 12 months old, pregnant dogs, dogs that are feeding puppies, or dogs used for breeding, unless your vet decides the benefits outweigh the risks.
Zenrelia affects the immune system, which can increase infection risk. Your vet will usually monitor your dog for infections and lumps, and recommend regular blood tests during long-term treatment. Tell your vet about any other medicines your dog takes, including steroids, ciclosporin and antacids.
Side effects
Vomiting and diarrhoea are the most common side effects, seen in 1 to 10 dogs out of every 100 treated. Inflamed paws and small skin growths called papillomas have also been reported. The full list is in the product datasheet.
Contact your vet if vomiting continues, or if you notice swelling, sores or growths on your dog’s paws or skin.
Legal Category: POM-V
View the Summary of Product Characteristics (SPC) information for this product
Zenrelia FAQs
Can you buy Zenrelia over the counter in the UK?
No. Zenrelia is a POM-V medicine, so you need a prescription from your vet. Once you have one, you can order here by uploading it at checkout.
Which Zenrelia strength does my dog need?
Your vet chooses the strength based on your dog’s body weight and writes it on the prescription. Please order the exact strength and quantity shown. If your dog’s weight changes a lot during long-term treatment, your vet may adjust the dose.
How quickly does Zenrelia work?
Ilunocitinib is absorbed quickly and reaches its highest blood level between 1 and 4 hours after a dose. How fast itching settles varies from dog to dog. Your vet will check how your dog is responding at follow-up appointments.
Can Zenrelia tablets be split?
Yes. Every strength has a score line on both sides and breaks into two halves. Store any leftover half in the blister and use it within 20 days.
Should Zenrelia be given with food?
It can be given either way. Giving it the same way each day, either always with food or always without, keeps absorption more consistent.
Can my dog have vaccinations while taking Zenrelia?
Talk to your vet before any vaccination. Zenrelia affects the immune system, and your vet will decide whether to give vaccines during treatment.
What’s the difference between Zenrelia and Apoquel?
Both are JAK inhibitors for itchy, allergic skin in dogs, but they contain different active ingredients: Zenrelia uses ilunocitinib, and Apoquel uses oclacitinib. Your vet will decide which suits your dog.
Instructions
Administer only as directed by your prescribing vet. The complete clinical datasheet is available below for your reference.
Instructions: Access the full product datasheet here for essential safety and administration information.
Sizes
Available pack sizes
- Pack of 30 Film-Coated Tablets
- Pack of 90 Film-Coated Tablets
Key Benefits
Ingredients
- Active Ingredient
Ilunocitinib
How it works to order pet prescription medications online
Choose your
treatment
Select the treatment you would like to order
Upload a prescription copy at
the checkout
Provide all the information about your pet
Express
Delivery
Your order will be sent in discreet packaging.
Frequently asked questions
Do I need a prescription to buy POM-V pet medicines online?
Yes. POM-V items require a valid prescription from your UK vet.
How do I send you my prescription?
Upload your prescription during checkout.
I uploaded a photo—why was it rejected?
Photos must be clear. If details are wrong or expired, orders can’t be processed. This is standard across UK pet pharmacies.
Can my vet refuse to give me a written prescription?
No. Under UK law, vets must provide a written prescription if you request one for a POM-V medicine. They may charge a reasonable fee for issuing it, but they cannot refuse. This allows you to choose where to buy your pet’s medication, whether directly from your vet or from a registered UK pharmacy such as Ashcroft 4 Pets.
How long is my prescription valid?
In the UK, most POM-V prescriptions are valid for 6 months, unless your vet specifies a shorter duration. Prescriptions for Schedule 2 or 3 controlled medicines are usually valid for 28 days and are not repeatable. At Ashcroft 4 Pets, we follow these same UK veterinary guidelines to ensure your pet’s medication is dispensed safely and legally.
How can I be sure Ashcroft 4 Pets is a safe and legitimate online pet pharmacy?
At Ashcroft 4 Pets, we are a fully VMD-registered and accredited online retailer. This means every prescription and over-the-counter pet medicine we supply is safe, genuine, and dispensed according to UK law.
We follow all Veterinary Medicines Directorate (VMD) rules, and our team checks every prescription carefully before processing. You can order with confidence, knowing your pet’s health is in the hands of experts and all medicines are traceable, legally supplied, and authentic.
How long can I continue ordering with my repeat prescription?
In the UK, most repeat prescriptions for POM-V medicines are valid for up to 6 months from the date your vet issues them. You can order multiple times within this period if your vet has authorised repeats.
For controlled medicines (Schedule 2 or 3), the prescription is valid for 28 days only and cannot be repeated. These medicines are strictly regulated due to their potential for misuse.
At Ashcroft 4 Pets, we follow UK law carefully, ensuring all prescriptions are dispensed safely, legally, and in the exact amounts prescribed.
What about “human” medicines prescribed for pets?
If your vet prescribes a human medicine for your pet under the Cascade, we can usually dispense against that prescription (with the right checks).
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