Expert: Ronald Levy, M.D. - 12/17/2007

Question
My husband is 69 and takes Levothyroxine, Cardizem CD and Lisinopril/Hydrochlorothiazide. I have read that you should tell the doctor all the medications you are taking before you have surgery. Why is this? Would any of the ones I listed interfere with the surgery?  Also, Several of them raise blood suger.  Could they raise it enough to be borderline diabetic? My husband has never had a problem with his blood sugar before, however twice now since he has been on Levothyroxin his blood sugar has been at a  pre-diabetic level when he has had blood tests done. His doctor had him get a four hour glucose tolerence test the last time which came back negative for diabetes.

Answer
We need to know because some of the drugs can affect the medications we give and also it often gives us insight into the severity of the underlying disease. It's not that they will interfere with surgery, it is that it will allow us to choose the best anesthetic plan for that case. As for drugs raising glucose, yes some drugs do have that side effect but they will not make him a diabetic. He needs to monitor these levels because hyperglycemia can be a problem but as long as he is being monitored, it is not a problem.

Ronald Levy, MD
Associate Professor of Anesthesiology
UTMB-Galveston