Beware Interactions Between Home Remedies and Medicine
Sixty-four year old
is a fervent believer in
the use of medicinal
herbs to treat or inhibit
conditions such as heart disease,
high blood pressure, high cholesterol,
colds, flu and other infections.
Stewart uses garlic, for example,
to treat chest pains. “I just cut up
the garlic and swallow it, or boil
it to make tea,” he said. He also
uses it to flavour his meals and
tenderize his meats. He is aware
that one should not ingest too
much garlic, but he believes
he has mastered the art of
“prescribing” his own dosage,
especially since the formula was
passed down from his ancestors.
But Stewart, like so many
Jamaicans, is unaware of the
potential interactions of medicinal
plants and foods with pharmaceutical
drugs. According to Dr.
Rupika Delgoda, head of the
Natural Products Institute (NPI)
at The UWI, Mona, this is quite
a common phenomenon. She
explained that about 23-25 per
cent of the Jamaican population
use pharmaceutical drugs in
conjunction with medicinal plants.
While this figure is not high, Dr.
Delgoda and her team at the
Natural Products Institute are
taking steps to educate people
about the dangers of mixing
herbs with certain prescription
drugs. Consequently, they
conducted two field surveys in
Jamaican pharmacies and one
house-to-house survey across the
general population. The individuals
in the pharmacy were persons
on prescription medication and
the survey sought to determine
whether these persons also selfmedicate.
“We found that 80 per
cent of them were actually using
a medicinal plant,” Dr. Delgoda
disclosed. “We also discovered
from all three surveys that only
18 per cent of the doctors were
aware of the fact that the patients
were taking it [the medicinal
Dr. David Picking, Research
Fellow at the NPI added that the
house-to-house survey revealed
that 72 per cent of the Jamaican
population use medicinal plants
on a day-to-day basis. That fact
motivated development of the
handbook. However, Dr. Picking
pointed out that the handbook,
titled “Potential Drug Interactions
for Commonly Used Medicinal
Plants & Foods in Jamaica, was
not compiled to discourage the
use of these plants and herbs,
but to support their safe use.
The handbook, a culmination of a
decade of research, was compiled
by Dr. Delgoda and Dr. Picking
specifically for healthcare professionals,
with their relevant
patients in mind. It provides a
list of 30 medicinal plants and
foods, along with 70 potential
drug interactions and several
guidelines for monitoring their use.
The handbook also includes the evidence on which the conclusions
are based. For example, garlic, scientifically known as Allium sativum,
may interact with antiplatelet and anticoagulant drugs, such as
Warfarin. An interaction with garlic may increase bleeding time.
According to the Handbook, the risk assessment is to monitor doses
of fresh garlic over three grams and to stop taking at least one week
before surgery. The evidence on which this is based includes reported
cases, clinical studies and anecdotal reports.
The handbook was officially launched on September 28, 2015 and is
currently available for purchase at the UWI Bookshop, as well as at
the Natural Products Institute. It is complemented by a user-friendly
app and website, which will provide a quick point of reference for
the medical community. NPI will also use the website to update
new findings on these natural products.
The Institute, an integrative research establishment within the Faculty of
Science and Technology, is also carrying out research on the efficacy of
herbs against cancer cells, as well as using natural products as cancer
treatment leads and prevention leads. Additionally, new research is
also being undertaken to understand the reason why mosquitoes,
particularly Aedes aegypti mosquitoes, are so resistant to the existing
insecticides on the market. The hope is to use natural products to
eradicate these known carriers of dengue fever, chikungunya virus
and zika virus.
In the near future, Dr. Delgoda also hopes to engage in research
towards commercialization of of natural products, as well as position
the Institute as an important academic partner and bridge for
businesses and industry.