I was never a fan of HCTZ for 2 reasons :
#1 there were hints that they interfered with insulin and increased the risk of developing Diabetes
#2 People taking HCTZ , slowly and silently, deplete body Potassium stores . This depletion
especially effects muscles.
Maintaing a normal blood potassium level is important for proper heart function.
Replacing the lost potassium is difficult .
Many people rely on eating a banana each day as their potassium source rather than
take a KCL supplement. One banana replaced some of the potassium but it would take one 40 inch
banana to replace all of the loss.
I became more aware of this total body potassium depletion problem, when patients taking HCTZ
or any diuretic ,was admitted to the hospital for an acute condition requiring IV fluids
Note: there are also thiazide -like diuretics , chlothalidone and Metolazone that have a similar action but have a different structure. Pay attention this may be important. keep reading.
There is an interesting article published in The American Journal Of Medicine (2011) 124,896-898
Half a Century of Hydrothiazide: facts , Fads ,Fiction , and Folly
Franz H. Messerti,MD and Sripal Bangalore,MD, MHA
I will just review the main points.
* Hydrochlorathiazide is the most commonly prescribed antihypertensive drug
* Antihypertensive Efficacy
They reviewed 19 studies with over 1400 patients and found that HCTZ in its usual dose 12.5
to 25mg/day reduced 24 hour ambulatory blood pressure 6.5 systolic/ 4.5 diastolic.
* Effect on Morbidity and Mortality
They found that there is no evidence that HCTZ in doses , of 12.5 to 25 Mg/day , reduced
myocardial infarction , Stroke , or Death
Higher doses ( 50 mg ) increased the risk of cardiac arrest
MRFIT ( multiple risk factor intervention trial ) Patients receiving HCTZ had a 46% increase
in cardiovascular mortality. Patients in the same study taking Chlorathalidone ( a thiazide- like )
had a 58 % decrease in mortality.
* Aherence to the Thiazides
A meta-analysis of 17 studies suggest that adherence to diuretics is worse than any other drug
class. One study found that only 39% of patients started on a diuretic remained on it at 1 year.
* Unpleasant side effects include
frequent urination , erectile dysfunction , fatigue ,leg cramps , muscle weakness due to low
Potassium plus the other things mentioned above.
This article gives me more reasons to avoid prescribing Hydrochlorothiazides( HCTZ).
A low salt diet may be a better choice .
Remember that a normal blood potassium may miss more serious potassium depletion
problems caused by diuretics .
Review your blood pressure medications and discuss side effects and Medication choices with
Have fun , Be Smart and be a wise informed consumer .