The side-effects of Apoquel

The side-effects data sheet for Apoquel state that if your dog has the gene for developing cancer, it will be ‘switched on’ when dosed with Apoquel!

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The side-effects of Apoquel

I have been prompted to write this article due to the concerning number of owners contacting me as their vets have prescribed Apoquel to treat their dogs itchy skin and they are very worried about giving it to their dogs. They have heard about the connection between cancer and Apoquel tablets.

Dangers of Apoquel chewable


Why do vets prescribe Apoquel?

Apoquel is a product that is used extensively in veterinary practices as it is so effective at controlling itching in dogs with hypersensitivities. It tends to be the first line of treatment used by vets when faced with a case of atopy or allergic dermatitis in dogs as it acts so fast in stopping a dog from being itchy.

The result is that an owner feels satisfied that the problem they came in for (an itchy uncomfortable dog), is being treated. Vets feel satisfied that they are able to provide a ‘quick fix’ to the problem in the space of 15 minutes  – which is the usual time that a vet has for a consultation.

It means that an owner feels relieved too that their dog has not been given cortisone tablets (as most owners are aware of the side effects of cortisone), and the veterinary practice can generate a healthy profit in the 15 minute consultation as Apoquel is an expensive drug and vets know that an owner will buy it directly from them and not from their pharmacy with a prescription as they want the immediate relief for their pets.

Why the concern about giving Apoquel?

Apoquel datasheet showing dangers to dogs
The highlighted areas in the side-effects data sheet for Apoquel state that in simple terms, if your dog has the gene for developing cancer, it will be ‘switched on’ when dosed with Apoquel.

More alarmingly however, is the side-effect of Apoquel if used in perfectly healthy dogs but given at higher doses than recommended as shown in this experiment in June 2022.  ALL the healthy 1 year old (young) Beagles given the high dose of Apoquel developed a lymphadenopathy ie the start of cancer as well as infections in their feet as shown in the section below from the data sheet!

4.10 Overdose (symptoms, emergency procedures, antidotes) (Read full date sheet in this link)

Oclacitinib tablets (Apoquel) were administered to healthy, one year old Beagle dogs twice daily for 6 weeks, followed by once per day for 20 weeks, at 0.6 mg/kg bw, 1.8 mg/kg bw and 3.0 mg/kg bw for a total of 26 weeks.

Clinical observations that were considered likely to be related to oclacitinib treatment included: alopecia (local), papilloma, dermatitis, erythema, abrasions and scabbing/crusts, interdigital “cysts”, and oedema of the feet.

Dermatitis lesions were mostly secondary to the development of interdigital furunculosis on one or more feet during the study, with the number and frequency of observations increasing with increasing dose. Lymphadenopathy of peripheral nodes was noted in all groups, increasing in frequency with increasing dose, and was frequently associated with interdigital furunculosis.
Papilloma was considered treatment related, but not dose related.

There is no specific antidote and in case of signs of overdose the dog should be treated symptomatically.
Amended: June 2022

What are the ingredients in Apoquel chewable tablets to make dogs find them appetising?

Pork liver powder
Crospovidone (type A)
Sodium starch glycolate (type A)
Glycerol monostearate 40-55
Sodium chloride
Xanthan gum
Brewer’s yeast dried
Silica colloidal anhydrous
Magnesium stearate

These ingredients are very concerning. As most dogs with skin sensitivities suffer from animal protein intolerances too, it does not make sense at all to produce a medication that could actually exacerbate the effects of sensitivity and cause more discomfort in these itchy dogs.

Pork is also known to be a type 1 carcinogen for us and our dogs and should NOT be fed – especially in medication and especially the liver which is where all toxins in a pig’s body concentrate!

Do you have an itchy allergic dog and you need further advice?


“I believe in a kinder, healthier way to feed our pets that does no damage to our environment, harms no animals and uses fresh, healthy plant-based ingredients for a balanced, wholesome and delicious diet”

Dr Arielle Griffiths Just Be Kind Dog Food



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