Glucocorticoids
• Effective
• Many routes of administration
Actions
• Redistribution of white blood cells
o Lymphopenia
o Neutrophilia
• Decreased vascular permeability
• Monocyte/macrophage function modulation
o Reduced cytokine production
o Phagocytosis inhibited
• Antibody production only reduced with long-term aggressive therapy
Side effects
• Most side effects are bothersome, but not dangerous to the patient
o Panting
o Thin skin
o Liver value elevation
o Polyphagia
o Pot belly
• PU/PD one of the most bothersome for the owners, consider DDAVP (1-2 drops BID, adjust dose to control signs)
• When serious side effects occur they are bad
o Colonic ulcers with spinal disease
o Although gastric changes are common with high dose therapy it does not seem to be a clinical problem
• PTE
• Pancreatitis
Cyclophosphamide
• Nitrogen mustard derivative
• Alkylating agent
o Cytoxic to resting and dividing cells
o Also chemo drug
• Inexpensive
• Commonly used as adjunctive therapy
Actions
• Cross links DNA to prevent replication of cells
• More pronounced in B lymphocytes (AB producers)
• Phagocytosis may also be inhibited
• Some question efficacy in immune-mediated disease, especially IMHA
Side effects
• Relatively rare, but when they occur they can be serious
•GI signs (rare)
• Bone marrow suppression (rare, but monitor CBCs regularly)
• Sterile cystitis (monitor UAs)
o Make sure patient is drinking lots and urinating frequently (usually not a problem since many are on glucocorticoids
concurrently, if it does occur it is a tough one to deal with
Dosage
• Usually 50 mg/M2 is used daily for 4 days, stop 3 days and then repeat therapy
• Every other day therapy is also possible
• I rarely use long term and now use it mainly for chemo
• Can be used in cats, not very safe though
Azathioprine
• Relatively inexpensive
• Used as an adjunctive therapy (cut pred faster)
• Side effects very rare, but when they happen they are bad
• My favorite adjunctive therapy with immune-mediated disease