This medication is available as an injectable from your veterinarian, an oral solution and oral . It also comes in eye drop formulations.
Uses of this Dexamethasone:
Dexamethasone is a member of the glucocorticoid class of hormones. It is a steroid similar to prednisone in its actions. This class, unlike the anabolic steroids used by some athletes to build muscle, these are catabolic steroids that have the opposite effect and break down muscle.
They break down stored resources (fats, sugars and proteins) so that they may be used as fuels in times of stress. Cortisone is a catabolic steroid naturally produced by the body. Dexamethasone is synthetic and can be given at calculated doses at precise times to help with inflammation and in some cases, immune mediated diseases.
In most cases, we do not use glucocorticoids for their influences on glucose and protein metabolism; we use them for their anti-inflammatory effects. Their uses fit into several groups:
- Anti-inflammatory – especially for joint pain and itchy skin.
- Immune-suppression – treating conditions where the immune system is destructively hyperactive. Higher doses are required to actually suppress the immune system.
- Cancer chemotherapy – although usually prednisolone, another steroid, is favored for this use.
- Central nervous system disorders – such as disc herniation to reduce swelling in the spinal cord.
Side Effects
Dexamethasone is commonly used for several weeks or even months at a time to get a chronic process under control. Once the condition is controlled, the dose is tapered to the lowest effective dosing frequency. The reason for this is that body will perceive these hormones and not produce any of its own. In time, the adrenal glands will atrophy so that when the medication is discontinued, the patient will be unable to respond to any stressful situation.
Additionally, abrupt discontinuation can cause a blood sugar crisis to result. By using the medication every other day or weaning off in a gradual taper, we allow the body’s own adrenal glands to resume normal activity.
Latent infections (such as feline herpesvirus) can be unmasked by dexamethasone or steroid use. Also, glucocorticoid hormone use can be irritating or even ulcerating to the stomach or intestine at higher doses and can cause ulcerations and performations when mixed with non-steroidal anti-inflammatory (NSAIDs) medications or aspirin.
Long-term steroid use strongly predisposes a patient to latent urinary tract infection. Such infections may not have apparent symptoms because the inflammation responsible for the symptoms is suppressed by the steroid.
Glucocorticoids are called diabetogenic hormones, which means that with long-term use or in predisposed patients they can cause diabetes. therefore, they should not be used in patients who already have diabetes mellitus.
Panting is a common corticosteroid hormone side effect.
Appetite loss, vomiting or diarrhea should be reported right away to your veterinarian.
Interactions with other Drugs
In addition to NSAIDs and aspirin, other medications can interact poorly with dexamethasone. A class of antibiotics called macrolides (such as clarithromycin or erythromycin) can increase dexamethasone blood levels. Use of the antifungal ketoconazole can have a similar interaction.
Diuretics that work by reducing blood potassium levels can create significantly low blood potassium levels when combined with dexamethasone.
Concerns and Cautions
Dexamethasone is considered to be a long-acting steroid, meaning that a dose lasts about two or two-and-a-half days. For this reason an every other day schedule is excessive for dexamethasone; every third day or less is the goal for dexamethasone.
The same salt retention that accounts for excessive thirst and urination may also be a problem for heart failure patients or other patients who require sodium restriction.
Diabetic patients should never take this medication unless there is a life-threatening reason why they must.
Glucocorticoid hormones can cause abortion in pregnant patients. This class of hormone should not be used in pregnancy.
Dexamethasone use is likely to change liver enzyme blood testing and interfere with testing for thyroid diseases.
Dexamethasone is approximately 10 times stronger than prednisone / prednisolone and is dosed accordingly by your veterinarian.
Monitoring tests will likely be recommended if this medication is used long term.
While steroids in the past were used for patients with allergies to alleviate itching, there are newer alternatives with fewer side effects have now become available and are often preferred.
