Side Effects Of Systemic Steroids In Dogs
Systemic steroids (oral pills and injections) in dogs can cause significant side effects that can impact quality of life, including increased drinking and urination, behavioral changes, and increased infection risk. Research shows that nearly 5% of dogs receiving systemic glucocorticoids experience documented side effects[6], with the most common being excessive thirst, increased urination, and digestive problems. Inhaled steroid alternatives offer the same therapeutic benefits with dramatically reduced side effects.
What to do next
Pick the next step based on where you are in the journey.
If your vet prescribed an inhaler…
Using a spacer chamber can help deliver medication more effectively and make treatment calmer at home.
Not sure yet?
Start with a quick symptom-focused checklist to organize what you’re seeing before your vet visit.
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 serious and significantly impact quality of life. 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 body[1]. 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 response[2]. 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.
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
- Dexamethasone[4]
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).
Quick check: when to seek veterinary care
- Urgent: severe lethargy, difficulty breathing, not eating/drinking
- Prompt visit: worsening symptoms that don’t improve in a week
- Bring notes: how long symptoms have been present and what triggers them
Note: these symptoms can overlap with other airway conditions (e.g., canine chronic bronchitis). A vet exam is the best next step to avoid treating the wrong condition.
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 skin[2]
In higher doses, corticosteroids are prescribed to treat autoimmune conditions and adrenal disorders in dogs such as:
- Addison's disease
- Lupus
- Autoimmune hemolytic anemia[5]
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 nausea[4]
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 disease[1]
If your vet prescribed an inhaler
Inhaled steroid therapy can be part of a vet-recommended at-home plan for canine respiratory conditions. A spacer chamber helps make delivery calmer and more consistent—especially for dogs who resist traditional dosing.
Limitation: this article is educational and can’t replace a prescription or a diagnosis. Your veterinarian determines whether inhaled therapy is appropriate and which medication is indicated.
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 Practice[4], 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.
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.
Does Your Dog Suffer From Canine Bronchitis?
Take the assessment to see if your dog may have canine bronchitis.
FAQs
The most frequently reported problems include excessive drinking and urination, increased appetite, panting, lethargy, vomiting, and increased risk of bacterial infections. Studies show these effects occur in up to 74% of dogs within just 5 days of starting treatment[7], making them extremely common rather than rare occurrences.
Short-term side effects like excessive thirst and urination typically appear within days of starting treatment, while long-term effects develop after weeks to months of use.
Extended use can lead to muscle weakness, poor wound healing, diabetes, Cushing's disease, urinary tract infections (affecting up to 30% of dogs), behavioral changes including aggression, and significantly increased susceptibility to bacterial and fungal infections throughout the body.
Inhaled corticosteroids avoid systemic absorption and go directly to the respiratory tract, meaning they don't circulate through your dog's entire body. Research demonstrates that dogs treated with inhaled steroids showed improvement in breathing symptoms without experiencing the drinking, urination, and behavioral side effects seen with oral medications.
Work with your vet to transition from oral to inhaled steroids for respiratory conditions, use the lowest effective dose for the shortest time possible, never stop steroids suddenly, monitor for increased drinking and urination, and consider alternative treatments for long-term conditions requiring more than 3-4 months of steroid therapy.
What to do next
Pick the next step based on where you are in the journey.
References
- Corticosteroids - Cleveland Clinic
- Steroid Treatment - Long-term Effects in Dogs - VIN
- Inhalation Therapy of Airway Disease - Merck Veterinary Manual
- Steroid Treatment - Long-term Effects in Dogs - VCA Hospitals
- Prednisone and Prednisolone for Dogs - DogTime
- Side Effects to Systemic Glucocorticoid Therapy in Dogs Under Primary Veterinary Care in the UK
- Perception and usage of short-term prednisone and prednisolone in dogs
