An October 2019 study by the University of Waterloo looked at impaired kidney function and hydration in a new computer model that, “simulates the muscle contractions that move urine from the kidney to the bladder.”
"People who have high blood pressure are typically given a water pill, so they pee a lot to lower their blood volume and in so doing lower their blood pressure … These patients are frequently also given another drug that targets a hormonal system which will affect the kidney as well.
"A lot of people are on these two drugs, and they will be fine. But one day they might have a headache and take an aspirin, and the three of these drugs together can hurt your kidneys."
“that unless a patient is properly hydrated, taking the two blood pressure drugs and an aspirin concurrently could cause acute kidney injury. The injury happens when there is an insufficient water balance, which can lead to concentrated urine from a build-up of waste in the body.”