Dexamethasone is a potent corticosteroid and immunosuppressant that treats an assortment of conditions, including inflammation, allergic reactions, arthritis, and cerebral edema. Vets sometimes use this medication as a diagnostic tool for dogs suspected to have Cushing’s disease.
Dexamethasone is available in 5 forms: oral tablets, liquid suspensions, eye drops and ointments, and injectable formulas for use in clinical settings. Tablets come in several dosages ranging from 0.25 mg to 6 mg. The exact dosage a pet needs depends on the condition. A dog taking dexamethasone for mild inflammation typically only needs 0.1 mg to 0.3 mg per lb. When using dexamethasone to suppress a canine’s immune response, vets prescribe a higher dosage, generally 1 to 3 mg per lb.
The cost of dexamethasone depends on the form and dosage strength. Generic tablets cost as little as 25¢ per tablet. The injectable solution ranges from $15 to $44 for a 2 mg/ml dosage and a 4 mg/ml dosage respectively. A 15 ml bottle of eye drops costs $30 on average. Eye ointment costs about $20.
According to the National Institutes of Health, studies of dexamethasone injections in lab animals found it’s 20 times more effective at controlling inflammation than prednisone and nearly 80 times more effective than hydrocortisone.
Contact your veterinarian if you notice any of the following side effects:
Changes in hair appearance
Loss of hair coat
Increase in body fat
Swelling of the abdomen
Excessive thirst or urination
Opportunistic infections (bacterial, viral, and fungal)
Swelling of the brain
Slow wound healing
Plaque deposits on the skin
Canines undergoing long-term corticosteroid treatment should have frequent check-ups to monitor their weight and bloodwork since these medications can worsen pre-existing conditions. Prolonged use of dexamethasone for dogs can cause electrolyte imbalances and abnormally high protein and blood glucose levels. Over time, a dog’s blood panels may reveal higher-than-normal liver enzyme levels and lead to steroid hepatopathy, a typically reversible condition caused by steroidal effects on the liver.
Dexamethasone isn’t recommended for puppies and adolescent dogs since it can adversely affect bone and cartilage development. This medication may also exacerbate medical conditions such as diabetes, stomach ulcers, Cushing’s syndrome, kidney failure, and low bone density.
Studies show that long-term treatment in dogs increases canines’ susceptibility to urinary tract infections. It’s estimated that 30% of dogs who take this drug for more than 90 days are diagnosed with a UTI. Most pet owners don’t even realize their dog is ill when taking dexamethasone because it masks the inflammation, pain, and other symptoms associated with UTIs. Most vets recommend that dogs on this medication for more than 3 months undergo regular urinalysis to make sure they remain healthy.
Dexamethasone is a known appetite stimulant and can predispose dogs to obesity and type 1 diabetes. Dogs who take this medication for an extended period should have regular check-ups to make sure their weight is within a healthy range.
Dexamethasone may interact with the following drugs:
NSAIDs (including aspirin, ibuprofen, and indomethacin)
Allergic reactions and sensitivity
Swelling of the face, tongue, or throat.
Frequently asked questions
My dog has been on dexamethasone for 2 months and seems to feel better. Should I stop giving them this medication?
No. Dogs who have been on this medication for more than 14 days must be tapered off. Consult with your vet about how to wean your dog off dexamethasone. 
Can you give dexamethasone to dogs who are pregnant?
This medicine is not intended for use in pregnant dogs. Dexamethasone is known to cause miscarriage, fetal death, preterm labor, and palette deformities in offspring.
How long do the effects of dexamethasone last for dogs?
Dexamethasone lasts for up to 2.5 days. Since it’s so long-acting, many vets instruct owners only to administer this medication every 2 to 3 days when used for an extended period.
My dog is panting a lot since starting dexamethasone. Is this normal?
Yes, panting is one of the most common side effects of this medication.
My dog seems hungrier than usual when they take dexamethasone. Should I be feeding them more?
No. Dexamethasone can cause weight gain in canines due to its effects on appetite. Feed your pet their usual amount, and if they still seem hungry, consider dividing their meals into smaller portions and feeding throughout the day.
How long does it take dexamethasone to start working for dogs?
Dexamethasone is a rapid-onset steroid and typically starts working within 1 to 2 hours.
How should I store dexamethasone for dogs?
Keep both tablets and liquid formulas at room temperature, away from UV light. Dispose of any remaining oral solution after 30 days of opening. Do not refrigerate or freeze dexamethasone liquid suspensions.