Direct comparison of doses did not show evidence of dose dependence for blood pressure-lowering for any of the other thiazides for which RCT data were available : bendrofluazide , chlorthalidone , cyclopenthiazide , metolazone or indapamide .
This is based on an informal indirect comparison of results observed in other Cochrane review s on ACE inhibitors , ARBs and renin inhibitors compared with placebo , which used similar inclusion /exclusion criteria to the present review .Thiazides reduced potassium , increased uric acid and increased total cholesterol and triglycerides .
These effects were dose-related and were least for hydrochlorothiazide .
Chlorthalidone increased serum glucose but the evidence was unclear for other thiazides .
This systematic review shows that hydrochlorothiazide has a dose-related blood pressure-lowering effect .
Thiazides reduced potassium , increased uric acid and increased total cholesterol and triglycerides
BACKGROUND Hypertension is a modifiable cardiovascular risk factor .
Although it is established that low-dose thiazides reduce mortality as well as cardiovascular morbidity , the dose-related effect of thiazides in decreasing blood pressure has not been subject to a rigorous systematic review .
It is not known whether individual drugs within the thiazide diuretic class differ in their blood pressure-lowering effects and adverse effects .
OBJECTIVES To determine the dose-related decrease in systolic and /or diastolic blood pressure due to thiazide diuretics compared with placebo control in the treatment of patients with primary hypertension .
Secondary outcomes included the dose-related adverse events leading to patient withdrawal and adverse biochemical effects on serum potassium , uric acid , creatinine , glucose and lipids .
Clonidine and guanfacine in hypertension
Guanfacine , 1 to 3 mg/day , and clonidine , 0.1 to 0.3 mg twice a day , were compared in a 24‐week double‐blind , r and omized , parallel study of 42 patients with hypertension that was inadequately treated by chlorthalidone , 25 mg/day .  Mean reduction of blood pressure was 18/9 mm Hg after guanfacine and 14/8 mm Hg after clonidine . To determine the incidence of rebound hypertension , subjects were hospitalized for 7 days during chlorthalidone therapy for collection of baseline data and once again immediately after abrupt withdrawal of the α‐agonist after 24 weeks of dosing . Although blood pressure and heart rate rose significantly in both groups , the changes after clonidine withdrawal were greater and occurred earlier ( day 2 ) than those after guanfacine withdrawal ( day 4 ) . Forty percent of the subjects receiving guanfacine and 64 % of subjects receiving clonidine  had diastolic blood pressure elevations ≥10 mm Hg from baseline . There were increases in urinary norepinephrine levels in both groups after drug withdrawal , but these correlated poorly with blood pressure rise . Side effects after guanfacine were much the same as those after clonidine . Guanfacine taken once a day provides an effective and safe alternative  to clonidine in the management of essential hypertension
Direct comparison of doses did not show evidence of dose dependence for blood pressure-lowering for any of the other thiazides for which RCT data were available : bendrofluazide , chlorthalidone , cyclopenthiazide , metolazone or indapamide .
This is based on an informal indirect comparison of results observed in other Cochrane review s on ACE inhibitors , ARBs and renin inhibitors compared with placebo , which used similar inclusion /exclusion criteria to the present review .Thiazides reduced potassium , increased uric acid and increased total cholesterol and triglycerides .
These effects were dose-related and were least for hydrochlorothiazide .
Chlorthalidone increased serum glucose but the evidence was unclear for other thiazides .
This systematic review shows that hydrochlorothiazide has a dose-related blood pressure-lowering effect .
Thiazides reduced potassium , increased uric acid and increased total cholesterol and triglycerides
BACKGROUND Hypertension is a modifiable cardiovascular risk factor .
Although it is established that low-dose thiazides reduce mortality as well as cardiovascular morbidity , the dose-related effect of thiazides in decreasing blood pressure has not been subject to a rigorous systematic review .
It is not known whether individual drugs within the thiazide diuretic class differ in their blood pressure-lowering effects and adverse effects .
OBJECTIVES To determine the dose-related decrease in systolic and /or diastolic blood pressure due to thiazide diuretics compared with placebo control in the treatment of patients with primary hypertension .
Secondary outcomes included the dose-related adverse events leading to patient withdrawal and adverse biochemical effects on serum potassium , uric acid , creatinine , glucose and lipids .