Moderate
Ciclosporin × Digoxin
Immunosuppressants. Calcineurin inhibitors×Cardiac glycosides (digitalis)
Mechanism
Ciclosporin inhibits P-glycoprotein in gut and renal tubules, reducing digoxin clearance. Digoxin AUC rises by 50–100%; toxicity risk is substantial.
Symptoms
Nausea, vomiting, loss of appetite, confusion, yellow-green halos around lights, arrhythmia (bigeminy, AV block). Symptoms appear earlier in older patients and chronic kidney disease.
Management
On ciclosporin start, reduce digoxin dose by 25–50% and check levels at 5–7 days. Target: 0.5–0.8 ng/mL. In parallel, monitor potassium and creatinine (ciclosporin is nephrotoxic and raises hyperkalaemia risk).
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.