Major
Ibuprofen × tacrolimus
Non-steroidal anti-inflammatory drugs (NSAIDs)×Calcineurin inhibitor (immunosuppressant)
Mechanism
Ibuprofen reduces renal blood flow via PGE2 inhibition. Tacrolimus is nephrotoxic in its own right. Additive acute kidney injury risk in transplant patients.
Symptoms
Reduced urine output, rising creatinine and potassium, oedema. Symptoms appear earlier in older patients and in chronic kidney disease.
Management
Avoid prolonged combination. For analgesia post-transplant, use paracetamol (up to 2 g/day) or a short opioid course. For neuropathic pain: gabapentin or pregabalin.