Expert: Dr. Ravindra Bhaskar Ghooi - 8/13/2009

Question
My father (75 years) has developed severe allergic rash for the past 3 months. I am suspecting that it could be due to Cozaar/Hyzaar which he has been taking for the past 18 months. He is also on Plavix, Crestor, folic acid.  I have ruled out Crestor as there was no changes after stopping taking it for 10 days. I am suspecting that it could be tha Hyzaar. What is the best way to find out. Should I stop him from taking it for 2 weeks or replace it with another drug? Please advise. Thank You

Answer
Hi Yap,
Actually you are on the right. The best way to find out is to stop the drug for a short while and see if the problem goes away. Hyzaar contains Losartan and Hydrochlorthiazide. In my reading I have felt that there is a greater incidence of allergy to hydrochlorthiazide. So I would replace Hyzaar first with its ingredients singly. That means stop hyzaar and take losartan tablets and hydrocholrthiazide tablets separtely. The stop Losartan and replace it with say Telmisartan. If that does nto help restart losartan, and stop hydrocholrthiazide and relace it with say lasix. This way you can test each drug separately.
Best wishes
Ravi Ghooi