A 35-year-old woman with systemic lupus erythematosus presents with lupus nephritis. Which medication is indicated for treatment of this complication?

• A. Cyclophosphamide
• B. Furosemide
• C. Hydroxychloroquine
• D. Ibuprofen

Answer: (A)

Lupus nephritis is driven by immune-mediated inflammation in the kidneys, so treating it requires suppressing the immune response rather than just addressing symptoms. For severe or proliferative nephritis, induction therapy uses a potent immunosuppressant to rapidly control inflammation and protect renal function. Cyclophosphamide serves this role well because it is a cytotoxic agent that dampens B- and T-cell activity, reducing autoantibody production and immune complex–driven glomerular injury. This targets the underlying disease process rather than merely relieving symptoms. By contrast, furosemide helps with edema but doesn’t address the immune attack. Hydroxychloroquine helps reduce disease flares in SLE and is used broadly, but it isn’t sufficient as the primary induction therapy for active nephritis. Ibuprofen can worsen kidney injury and is avoided in nephritic states. Thus, cyclophosphamide is the appropriate choice for treating lupus nephritis.