Why can't you take prescription medications with grapefruit?
Grapefruit is a good source of vitamin C and the antioxidant lycopene. But the citrus...
Grapefruit is a good source
of vitamin C and the antioxidant
lycopene. But the citrus
fruit also contains chemicals that
interfere with the enzymes that
normally break down drugs in
your digestive system. When
those enzymes fail to do their job,
the drug enters your bloodstream
at higher-than-acceptable levels,
increasing your risk of developing
side effects.
Until last year, scientists
blamed the flavonoids found in
grapefruit as the source of interference.
But a study published
last May in the American Journal
of Clinical Nutrition discovered
that a group of natural chemicals
called furanocoumarins were
the likely culprit. The study compared
the effects of orange juice,
regular grapefruit juice, and
furanocoumarin-free grapefruit
juice on 18 people taking Plendil,
a drug used to treat high blood
pressure. Blood levels of Plendil
were higher when the drug was
taken with regular grapefruit
juice, but not with orange juice or
furanocoumarin-free juice.
Grapefruit most commonly
interacts with drugs taken for
high blood pressure, high cholesterol,
depression, anxiety, allergies,
HIV, impotence, and seizures.
If you're taking medication for
any of these conditions, avoid
grapefruit as a snack or juice. To
be on the safe side, also stay away
from tangelos, which are a hybrid
of tangerine and grapefruit.
-Gina L. Nick, N.M.D., Ph.D.,
medical director at Serenity
Wellness Center (serenitywellnessctr.com) in Costa Mesa, Calif.
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