Deflazacort (Calcort) is a glucocorticoid drug primarily used for the treatment of Duchenne muscular dystrophy (DMD) as well as other inflammatory or autoimmune diseases. Although its efficacy is well-established, long-term use may be accompanied by a variety of side effects, requiring strict monitoring.
What Are the Side Effects of Deflazacort (Calcort)?
Metabolic and Endocrine System Effects
Cushing’s Syndrome Manifestations: Moon face, centripetal obesity, and fluid retention.
Increased Blood Glucose: May induce or exacerbate diabetes; regular blood glucose monitoring is required.
Electrolyte Imbalance: Hypokalemia and hypertension (incidence of approximately 10%–20%).
Gastrointestinal Reactions
Increased appetite (common in children) and dyspepsia (incidence of 5%–10%).
Long-term use may cause gastric ulcers (concomitant use of gastric mucosal protectants is necessary).
Skeletal and Muscular Effects
Osteoporosis: Children and patients on long-term medication need supplementary calcium and vitamin D.
Exacerbated Muscle Weakness: For DMD patients, the balance between therapeutic effects and the risk of deteriorating muscle function must be considered.
Other Common Reactions
Headache (incidence of 5%–15%), mood swings (e.g., anxiety, depression), and thinning of the skin.
Severe Side Effects of Deflazacort (Calcort) That Require Vigilance
Adrenal Suppression
Sudden discontinuation after long-term use may lead to adrenal crisis (manifested as hypotension and shock).
Management Measures: The drug must be discontinued gradually by reducing the dose; abrupt discontinuation is not allowed.
Increased Infection Risk
May mask infection symptoms, leading to worsening bacterial, fungal, or viral infections (e.g., pneumonia, herpes zoster).
High-Risk Populations: Immunocompromised patients or those receiving concurrent treatment with other immunomodulators.
Ocular Complications
Cataracts (incidence of approximately 5%–10% in pediatric patients) and glaucoma.
Monitoring Recommendations: Ophthalmic examinations should be conducted every 6 months.
Precautions for Administration of Deflazacort (Calcort)
Contraindications in Special Populations
Children: Close monitoring of growth retardation and changes in bone mineral density is required.
Pregnant Women: Should be used only when there is a clear medical need (FDA Pregnancy Category C).
Lactating Women: The drug may be excreted into breast milk; it is recommended to discontinue the drug or terminate breastfeeding.
Drug Interactions
CYP3A4 Inhibitors (e.g., clarithromycin): May increase the plasma concentration of deflazacort, requiring dose reduction.
Live Vaccines: Vaccination is prohibited during medication administration (immune response may be weakened).
Key Points for Long-Term Management
Monitoring Items: Regularly check blood pressure, blood glucose, bone mineral density, and electrolytes.
Evaluate growth curves every 3–6 months (for pediatric patients).
Lifestyle Interventions: Adopt a low-salt, high-protein diet and engage in moderate exercise to prevent muscle atrophy.

