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Date of last update: 10/20/2017.

Forum Name: Hypertension

Question: If HCTZ discontinued, how long till no effect?

 WilliamR - Fri Jan 25, 2008 1:15 pm

I am currently on multiple BP medications - one of which HCTZ - my Doctor and I are considering discontinuing the HCTZ due to potential blood glucose impacts.

My question is- IF I discontinue HCTZ, how long will it be before that drug is no longer having any residual reduction affect on my BP?

I don't want to discontinue HTCZ, check my BP for a few days and think all is OK, only to check my BP a month later and find that it has soared.

Thank you!
 Dr. Chan Lowe - Thu Feb 07, 2008 9:29 pm

User avatar Hello WilliamR,

A good rule of thumb is that in 5 half lives a drug has reached the new steady state of where the concentration will be with the current dosing. So using this same rule, 5 half lives will result in no further effect.

The half life of HCTZ is anywhere from about 6 to 15 hours, with it being closer to six in most people. So it ranges from about 1 & 1/2 days to a little over 3 days before the effect will be gone.

Best wishes.

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