Side Effects Of Systemic Steroids In Dogs

Systemic steroids are a common prescription for dogs, used to treat certain conditions like allergies and autoimmune diseases. For dogs with bronchitis or other respiratory diseases, corticosteroids are used for daily disease management.

The problem is these medications can have many unwanted side effects when given by mouth or by injection, some of which can be life-threatening. Thankfully, alternative delivery options exist.

What Are Corticosteroids?

Corticosteroid medications are synthetic drugs that mimic cortisol, a glucocorticoid hormone that is naturally produced by the body¹. Cortisol is a stress hormone that helps regulate various systems in the body (such as controlling blood pressure and sugar levels) and acts as anti-inflammatory agent.

Similarly, synthetic corticosteroid medications help reduce inflammation and, in higher doses, suppress or prevent the immune response². These steroid medications are prescribed to manage inflammation and immune function in dogs and must be used regularly in order to be effective.

What Are Systemic Steroids?

Systemic steroids are corticosteroid medications that are taken by mouth (pills or liquids) or injection. These medications need to be metabolized by the body before they take effect and, once in the bloodstream, are carried throughout the body. As a result, only some of the medication reaches the target area, while the rest can impact other organs and cause many unpleasant or dangerous side effects.

Large dog laying down looking at hand holding a pill in foreground.

Injections are usually administered by a vet in an emergency situation to get serious symptoms under control. Oral steroids may be prescribed to treat and manage your dog’s conditions at home, although they should not be used long term.

What Are Inhaled Steroids?

Inhaled steroids are medications that are prescribed to treat respiratory conditions in dogs and administered by inhaling the medication through a nebulizer or a metered dose inhaler.

Inhaled steroids are different than oral or injected steroids as they do not need to be metabolized by the body, allowing the medication to directly target the lungs or respiratory tract. As a result, inhaled steroids have a very low risk of side effects and are considered safe for long-term use.³

Types Of Systemic Corticosteroids For Dogs

The main types of oral steroid medications prescribed for dogs include:

Prednisone
Dexamethasone⁴

Depo medrol for dogs (Pfizer, methylprednisone) and dexamethasone are injections used to get severe symptoms under control (such as when your dog is having extreme difficulty breathing).

What Are Steroids Used For In Dogs?

Steroid medications are commonly used for treatment of a variety of conditions in dogs, but dosage and duration of medication differ depending on the nature of your dog’s condition.

In lower doses, corticosteroids are used to treat inflammation associated with:

Bronchitis
Other respiratory conditions
Allergies
Joint pain
Itchy skin⁵

In higher doses, corticosteroids are prescribed to treat autoimmune conditions and adrenal disorders in dogs such as:

Addison’s disease
Lupus
Autoimmune hemolytic anemia⁶

What Are The Side Effects Of Systemic Steroids In Dogs?

Systemic steroid use in dogs affects almost all the systems in the body, resulting in a high risk of potentially serious side effects.

Canine Prednisone, Prednisolone, And Dexamethasone Side Effects

Short Term Side Effects

Increased thirst and appetite
Frequent urination
Panting
Lethargy
Development or worsening of infections (especially bacterial skin infections)
Vomiting or nausea⁷

Long Term Side Effects

Behavior changes, including aggression
Urinary tract infections (UTIs)
Thin skin and poor hair coat
Poor wound healing
Obesity
Muscle weakness
Increased risk of developing secondary bacterial or fungal infections
Predisposition to diabetes
Cushing’s disease⁸

Brown labrador dog resting his head on the arm of a couch.

Should Dogs Take Systemic Steroids Long Term?

Systemic steroids should not be used for long term treatment due to the high risk of serious side effects. If oral steroids are required for a longer duration, your dog’s condition should be re-evaluated and different treatment options should be considered.

For dogs with chronic respiratory issues, systemic steroids are normally used to get serious symptoms under control before transitioning to inhaled steroids.

Why Inhaled Steroids Are Preferred

For dogs who suffer from chronic canine bronchitis or other respiratory diseases, steroids are an important component to daily disease management. Inhaled corticosteroids can greatly reduce side effects and promote a higher quality of life for your dog and your family.

In a study published in the Journal of Small Animal Practice⁹, inhaled corticosteroid therapy was shown to be well tolerated in dogs and reduced or resolved symptoms of canine respiratory disease without obvious side effects.

Inhaled corticosteroids are easy to administer to dogs, can be done at home, and without the need to hide pills in food. The use of a spacer device (such as the AeroDawg* canine aerosol chamber) can provide fast, effective results with lower doses of drug while ensuring your dog is able to breathe in the medication in multiple breaths.

Corgi mix dog outside next to blue flowers.

How To Protect Your Dog From Side Effects Of Steroids Long-Term

Inhaled corticosteroids are potentially life-saving medications and can greatly improve a dog’s quality of life. If your dog is suffering from a chronic respiratory condition such as bronchitis, speak with your vet about transitioning your pet to inhaled corticosteroid therapy in conjunction with the AeroDawg* canine aerosol chamber to manage their condition.

Learn more about canine bronchitis and treatment options to manage your dog's quality of life and keep them healthy long term.