Methylprednisolone

What is methylprednisolone?

Methylprednisolone (brand names: Medrol®, Depo-Medrol®, A-Methapred®, Solu-Medrol®) is a glucocorticoid steroid medication used to treat many inflammatory conditions, adrenal gland disease, and immune-mediated disease. It is similar to but slightly more potent than prednisone/prednisolone. 

While some uses for dogs, cats, and horses are on label, its use to treat some other disorders is off label (extra label). Many drugs are commonly prescribed for off-label use in veterinary medicine. 

“Off label” means the drug is being used in a way that has not been reviewed or approved by the U.S. Food and Drug Administration (FDA) or Health Canada. In these instances, follow your veterinarian’s directions and cautions carefully, as they may be significantly different from those on the label. 

How is methylprednisolone given?

• Methylprednisolone is given by mouth in the form of a tablet or a specially compounded liquid. It can also be given as an injection in the hospital or clinic setting.
• Measure liquid forms carefully.
• Give with food. If given once daily, give it in the morning for dogs and horses and in the evening for cats.
• Do not stop this medication abruptly without consulting with your veterinarian. 

This medication will take effect quickly, in about 1 to 2 hours, and improvement in clinical signs should follow. 

What if I miss giving my pet the medication?

If you miss a dose, give it as soon as you remember, and then continue with the regular dosing schedule. However, if it is almost time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not give the pet two doses at once.

Are there any potential side effects?

Methylprednisolone may cause the following side effects at any dose:

• Increased drinking and urination
• Increased appetite

Other side effects may occur, usually at higher doses, especially in dogs, including:

• Dull/dry haircoat
• Weight gain, pot-bellied appearance
• Muscle weakness
• Panting
• Vomiting
• Diarrhea
• Elevated fat or liver enzymes in the blood

Serious adverse reactions may occur, including stomach ulcers and bleeding. If any of the following signs develop, stop giving methylprednisolone and contact your veterinarian immediately:

• Black, tarry stools
• Bloody vomit, black specks like coffee grounds in the vomit
• Frank blood in the stools
• Loss of appetite
• Fever
• Secondary infections
• Inflammation of the pancreas
• Activation or worsening of diabetes mellitus
• Muscle wasting
• Severe changes in behavior

This medication can also interfere with certain laboratory tests, including:

• Cortisol tests
• Blood cholesterol
• Urine and blood glucose (sugar) levels
• Potassium levels
• Thyroid hormones
• Skin tests
• White blood cell counts

Other side effects may occur. If you notice anything unusual, contact your veterinarian immediately. This moderate-acting medication should stop working in a few days, although effects can be longer in pets with liver or kidney disease.

Are there any risk factors for this medication?

DO NOT USE methylprednisolone in pets that:

• Are allergic to it
• Have systemic fungal or viral infections
• Have diabetes or Cushing’s disease
• Have stomach or intestinal ulcers
• Are also receiving non-steroidal anti-inflammatory drugs (NSAIDs)
• Are recovering from a recent surgery

USE WITH CAUTION in:

• Dogs (can cause gastrointestinal complications and bleeding)
• Pets predisposed to diabetes mellitus (especially cats)
• Pets with kidney disease or heart disease
• Pets with general bacterial or fungal infections
• Pets with high blood pressure
• Pets that are pregnant or lactating
• Young animals (can slow growth)

Do not stop this medication abruptly after long-term use (greater than 2 weeks); taper slowly to avoid complications.

Are there any drug interactions I should be aware of?

Several medications should be used with caution when given with methylprednisolone, including:

• Anticholinesterase agents
• Aspirin
• Azole antifungals
• Barbiturates
• Bupropion
• Cyclophosphamide
• Cyclosporine
• Insulin
• Macrolides
• NSAIDs
• Phenobarbital
• Potassium-depleting diuretics
• Theophylline
• Vaccines

Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment.

Is any monitoring needed with this medication?

• Depending on the reason for use and other factors, a variety of monitoring may be indicated, such as weight, appetite, signs of swelling, electrolyte levels, blood protein levels, blood glucose, growth and development (young animals), and an ACTH stimulation test.
• Your veterinarian may monitor your pet to be sure that the medication is working.

How do I store methylprednisolone?

• Store the tablets at room temperature between 59°F and 86°F (15°C and 30°C) and protect from light.
• Store compounded forms of the medication according to the label.

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. Be prepared to provide information about the product and your pet's weight and symptoms.