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Apoquel for Dogs – Side Effects and Safety

Apoquel for dogs was originally created as a short-term solution to treat dermatitis. Common side effects in dogs can include vomiting, diarrhea, lethargy, and anorexia. 

Not all dogs will have these side-effects, and those who do will likely be limited to gastrointestinal issues.

One benefit of administering apoquel for dogs is for relief of intense itch. Getting rid of the intense itch caused by dermatitis helps the body to rest. Proper rest and nutrition work hand-in-hand to increase immunity, which is exactly what your dog needs

Possible Severe Side Effects of Apoquel for Dogs

Severe side effects include increased cholesterol and lipase, low white blood cells and decreased globulins.

Rare side-effects could also include aggression and a heightened appetite.

Some dogs will develop more lumps and bumps and may develop ear and urinary tract infections. This drug should not be given to dogs under the age of 12 months.

The veterinarian’s job is to address the cause of the itch and provide relief for your dog as soon as possible. Apoquel, which is known to work quickly, is sometimes the best choice.

If the veterinarian thinks your dog would benefit from taking Apoquel beyond 14 days, he/she will assess your dog’s health and reduce the dosage.

Getting Ahead of Skin Problems in Dogs

The best way to avoid prescription drugs like Apoquel is to try and get ahead of skin conditions. It’s not always possible to do this, but using a top-graded product that comes with veterinarian approval could do wonders.

Vetionx – Professional Grade Veterinary Products for Pets

Vetionx is a company that produces clinical grade products that are homeopathic and safe.

One of their best selling products, Derma-ionX, is a proactive step towards calming skin irritations before they get out of control.

The following video shows a live before/after effects of Apoquel in Dogs. It’s worth a look!

Brighton: Apoquel treatment for IMPA (before/after)

The Truth about Apoquel Side Effects in Dogs

Apoquel (brand name Oclacitinib) was FDA approved in 2013 for use in dogs with atopic and/or allergic dermatitis. All drugs come with risks and, unfortunately, a small minority of dogs will have more severe side effects.

The Food and Drug Administration accepts reports from veterinarians whose animals have experienced some of the more severe side effects.

Reports submitted to the database take into account the dosage and diagnosis. In addition, things like product defects are considered.

Adverse Drug Effects Reporting 

The FDA currently maintains a database of reported Apoquel side effects in dogs. The information comes from the Center for Veterinary Medicine and is kept updated monthly.

As of October 14th, 2018, there was no report submitted to the database on any side effects (mild to severe) on Apoquel. That included a search using the brand name “Apoquel” and the generic name “Oclacitinib”.

The most common side-effect noted on the product insert is gastrointestinal upset which may resolve on its own.

Apoquel hasn’t been evaluated for use in combination with steroids or other immune suppressing drugs.

 A Note on Bone Marrow Suppression

Bone marrow is the soft tissue found in the middle of long bones.  If you’re worried about immune system suppression, this is where it starts. 

Red blood cells, white blood cells, and platelets are generated in bone marrow and released into the blood stream. 

STATISTIC: Only 1% of pets on Apoquel have shown bone marrow suppression.

These are initially created from stem cells, which then develop into blood cells. The type of blood cells formed are based on what the body requires.

Bone marrow suppression (myelotoxicity) decreases the production of blood cells. 

Suddenly, the white blood cells that would normally fight infection are unable to do their job. 

Other drugs that can induce immune suppression include some antibiotics, non-steroidal anti-inflammatory drugs (in rare cases) and drugs used to treat chemotherapy can induce blood marrow suppression.

Don’t Miss Follow-Up Appointments

If your veterinarian prescribes Apoquel for your dog, make sure to stick with the follow-up appointments. He/she will want to monitor your dog to watch for adverse effects.

If any major side effects occur, the veterinarian can take steps to reduce dosage or recommend another course of treatment.

Concerned Veterinarians Take a Closer Look

In 2015, when Apoquel was fresh off the shelf, a round table discussion was held at the North American Veterinary Dermatology Form in Nashville, TN. 

A team of veterinarian professionals came together to discuss reported Apoquel side effects in dogs.

Overall, it was felt that Apoquel for dogs was well tolerated. 

The concerns they had included weight gain, demodicosis, warts, urinary tract infections, loss of protein in the urine, low white blood cell counts, elevated liver values, and rectal bleeding.

NOTE: Rectal bleeding was seen in 3 patients and doctors were not able to determine that it was caused by Apoquel.

Some patients (dogs) developed malignant tumors.  However, none of the participants felt that Apoquel was to blame.

One dog suffered a heart attack (5 year old Labrador). However, it couldn’t be determined whether Apoquel was the cause.

At the end of the day, participants suspected Apoquel may have contributed to interdigital cysts, pneumonia, and fungal infections.

Large, light brown dog appears bothered by the tall grass he is sitting in.

Does Dosage Affect Apoquel Side Effects in Dogs?

Any drug administered beyond the recommended dosage could create unwanted side-effects. 

Apoquel side effects in dogs are not well-documented using high doses. Generally, Apoquel is administered twice per day for 14 days.  If required over a longer period, the dose is alternated every other day.

Dosage depends on the size of the dog. Large breeds between 130 and 175 pounds would be given 16 mg.

Small breeds would only take a half tablet and the dogs that fall in between would take one tablet.

REMEMBER: Your veterinarian will give the appropriate dosage instructions based on the unique breed and health condition of your dog.

Is There an Apoquel Alternative for Dogs?

There are no good alternatives to Apoquel that meet its unique formulation. There are other options for atopic dermatitis, but each drug has its own unique side effects.

Is it True That Apoquel for Dogs Causes Cancer?

The reality is that there are no “miracle drugs” on the market.  Side-effects occur in just about every medicine.  In most cases, Apoquel side effects in dogs are mild. The most commonly reported side effects are gastrointestinal upset.

Apoquel, however, is still relatively new and long-term studies have yet to be confirmed.  

Beating Down the Immune System

Suppressing the immune system doesn’t make sense until you understand why it’s done. The first thing to understand is how allergies work.

To be allergic to something means that your body’s defences overreact when exposed to certain things like dust, mold, grass, certain foods, etc. In people, one example of a severe allergic reaction would be anaphylaxis.

These are people who are so severely affected by things like bee stings, peanuts, or seafood that they have to carry an Epi-Pen.  That’s because their immune system overreacts to certain allergens.

Histamines are the Culprit

Histamine is produced by the granules in mast cells and basophils cells (type of white blood cells).

These elements respond to the presence of invading bodies by releasing histamine through the bloodstream. It’s completely normal for the body to do this. In fact, it’s the body’s way of protecting itself against foreign elements.

In people, histamines are released when you have a cold virus, for example. The body signals itself to make more mucus and to protect the thin nasal walls with thick secretions. It does this to allow other chemicals to step up and clean out the virus or bacteria. 

Unfortunately, in some people – and dogs – the reaction is overkill. Excessive amounts of histamine are released causing symptoms like extreme itch and swelling. When this happens to dogs, the skin becomes unbearably itchy. Naturally, the dog scratches the itch.

Over time, the skin barrier breaks open leaving it vulnerable to bacteria. Not only is your dog miserable, but now he has to be treated for a secondary infection

You can treat mild itch with a variety of over-the-counter creams, gels, and lotions. There are a variety of things on the market, including oral supplements, that can help. 

The problem comes when you’re dealing with a systemic problem that goes beyond the typical (mild) allergic reaction.  

What You Need to Know About Suppressing the Immune System.

When talking about Apoquel side effects in dogs, people often refer to the dangers of suppressing the immune system.

What you have to remember is that the immune system of a dog with atopic dermatitis is already over-producing histamine. Histamine is the major element in allergic reactions. It’s the thing that causes the severe itching.

In order to adequately protect the skin barrier, the immune system needs to be tamed.

In the short-term, that’s actually a good thing. In fact, it’s the factor that leads to many veterinarians prescribing Apoquel in the first place.

Apoquel is approved for short-term use and within that 14 day period, you’re probably not going to witness any serious side effects.

Once your dog has been on Apoquel longer, the veterinarian will start watching for signs of bone marrow suppression or serious infection.

Apoquel Just Isn’t Enough

Unless the dog’s condition is treated effectively, Apoquel will just mask the problem.  Yes, it will take care of the itch which will allow the skin to heal.  But what happens when you stop the medication?

If the veterinarian can determine the cause of your dog’s allergies, steps can then be taken to treat those allergies.


It’s easy to get a monthly topical prescription that will eradicate fleas.

Ticks? Gone. Allergic to certain foods? Gone.  Some dogs, however, have serious allergies that aren’t that easily taken care of.

Severe itching in dogs isn’t unusual. The problem is when the dog begins to bite and chew the skin.

Inflammation, cracked skin, and infection can settle.  Atopic dermatitis is caused by an allergic reaction to things like dust, mold, grass, certain foods, etc.

The veterinarian may want to try eliminating known allergens while supplementing treatment with corticosteroids. 

Topic creams or shampoos are available to help stop itch.  None of them, however, are as fast-acting as Apoquel.

How Drugs Like Apoquel Make it to Market

Clinical tests and trials must be done before the FDA will approve a drug for human

FDA Approval Process

The FDA must make sure that the drug in question has been reviewed by the Center for Drug Evaluation and Research.

In addition, the drug has to be shown to provide benefits that outweigh risks.

A structured framework for drug approval involves:

-Analysis of the target condition and available treatments

-Assessment of benefits and risks from clinical data

It Boils Down to This

Understanding the risks of any drug is important, just don’t buy into fear from anecdotal evidence.  Yes, serious Apoquel side effects in dogs can happen. However, with careful monitoring by an experienced veterinarian, the risks are minimized.

If you decide to give your dog Apoquel, be consistent with the treatment and do not stop suddenly. Communicate with your veterinarian for the best possible outcome. 

Still worried about immune function and side effects? Talk to your veterinarian about supplementation to keep the immune system as strong as possible. 

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