In summary , the current meta- analysis demonstrated that melatonin supplementation  significantly decreased SBP and DBP in patients with metabolic disorders .
The current systematic review and meta- analysis of r and omized controlled trials ( RCTs ) was conducted to evaluate the potential effect of melatonin supplementation on  blood pressure in patients with metabolic disorders .
Cardiovascular effects of melatonin in hypertensive patients well controlled by nifedipine: a 24-hour study.
AIMS As melatonin has been found to play a role in the mechanisms of cardiovascular regulation , we design ed the present study to evaluate whether the evening ingestion of the pineal hormone might interfere with the antihypertensive therapy in hypertensive patients well-controlled by nifedipine monotherapy . METHODS Forty-seven mild to moderate essential hypertensive out patients taking nifedipine GITS 30 or 60 mg monotherapy at 08.30 h for at least 3 months , were given placebo or melatonin  5  mg at 22.30 h for 4 weeks according to a double-blind cross-over study . At the end of each treatment period patients underwent a 24 h noninvasive ambulatory blood pressure monitoring  ( ABPM ) during usual working days ; sleeping period was scheduled to last from 23.00 to 07.00 h. RESULTS The evening administration of melatonin induced an increase of blood pressure and heart rate throughout the 24 h period ( DeltaSBP = + 6.5 mmHg , P < 0.001 ; DeltaDBP = + 4.9 mmHg , P < 0.01 ; DeltaHR = + 3.9 beats min-1 , P < 0.01 ) . The DBP as well as the HR increase were particularly evident during the morning and the afternoon hours . CONCLUSIONS We hypothesize that competition between melatonin and nifedipine , is able to impair the antihypertensive efficacy of the calcium channel blocker . This suggests caution in uncontrolled use of melatonin in hypertensive patients . As the pineal hormone might interfere with calcium channel blocker therapy , it can not be considered simply a dietary supplement
In summary , the current meta- analysis demonstrated that melatonin supplementation  significantly decreased SBP and DBP in patients with metabolic disorders .
The current systematic review and meta- analysis of r and omized controlled trials ( RCTs ) was conducted to evaluate the potential effect of melatonin supplementation on  blood pressure in patients with metabolic disorders .