Repeated melatonin reduces night-time blood pressure
Repeated doses of melatonin reduce nocturnal blood pressure, a new study shows.
The finding suggests that enhanced functioning of the biological clock
could one day be used as a strategy for the treatment of
hypertension.
Researchers from the Netherlands Institute for Brain Research, Amsterdam,
examined the effect on blood pressure of a single dose of oral melatonin
(2.5mg) and that of repeated doses
(2.5mg daily for three weeks) given one hour before bedtime. They found
that, compared with placebo, repeated doses reduced systolic and diastolic
blood pressure during sleep by 6mmHg and 4mmHg,
respectively.
A single dose of melatonin had no effect on blood pressure.
“Support of circadian pacemaker function may provide a new strategy
in the treatment of essential hypertension,” they suggest. However,
the researchers acknowledge that improved sleep, reported by patients
taking melatonin, could have helped reduce blood pressure.
The crossover study, which involved 16 men with untreated essential hypertension,
is published
online in the rapid access issue of Hypertension.
Dan Jones, a spokesman for the American Heart Association, said that
the report was of interest primarily at a research level. “Larger
studies certainly would be needed prior to recommending this approach
to patients with high blood pressure,” he added. |
The
Pharmaceutical Journal