The exact cause of Ibuprofen-induced renal tubular acidosis isn’t fully understood, but is thought to involve a reduction in the activity of carbonic anhydrase; Particularly carbonic anhydrase type II, which is mainly found in the kidneys. This leads to a hyperchloraemic metabolic acidosis, where the kidneys are unable to properly acidify the urine. The hypokalaemia that often accompanies this condition is believed to occur because the acidosis affects the reabsorption of sodium in the proximal tubules, which in turn increases potassium loss in the distal tubules.
