TB pills most effective prior to, not after, food: research
A team from National Institute for Research in Tuberculosis (NIRT) examined 25 TB patients in Chennai who consumed food just before they took their medication.
In a study that could change the intake schedule of tuberculosis
drugs, a group of researchers have found that food reduces the
effectiveness of most medicines prescribed as the first line of
treatment for the infection.
A team from National
Institute for Research in Tuberculosis (NIRT) examined 25 TB
patients in Chennai who consumed food just before they took
their medication. They found significantly lower concentrations
of anti-TB drugs and a delay in their absorption. They studied
the concentrations of three key first-line drugs: rifampicin,
isoniazid and pyrazinamide.
Dr Soumya Swaminathan,
director general of Indian Council of Medical Research and one
of the co-authors of the study , said though most doctors are
aware of the clinical impact of food on rifampicin, guidelines
on when to take the other drugs are hazy .
“Our
study shows that at least two other first-line drugs need to be
taken on fasting,“ she said, adding that the findings are
significant as the dosage of first-line drugs is low.
But
not everyone can tolerate these drugs on an empty stomach.
“In such cases, a gap of at least three hours after food
[is ideal],“ she said.
The research, which was
published in Indian Journal of Medical Research, involved
studying patients who took their pills after breakfast. The same
group was examined after a 12-hour over night fast, followed by
drug administration and breakfast two hours later.
The
researchers found drug administration with food caused the
plasma concentration (time taken for drug to start taking effect
after absorption in blood) to decrease by 50%, 45% and 34% for
rifampicin, isoniazid and pyrazinamide, respectively.
Researchers
say food intake exerts a complex influence on drug
bioavailability .
“It may interfere not only
with tablet disintegration, dissolving of drugs and drug transit
through the gastrointestinal tract but may also affect metabolic
transformation of drugs in the gastrointestinal wall and
liver,“ said Dr Geetha Ramachandran, of the department of
biochemistry and clinical pharmacology at NIRT.
She
said there is no clear guidance on whether or not to take
anti-TB medication with food. "It is believed that drugs are not
well tolerated on an empty stomach and many patients prefer to
have food before they take medicines," she said.
Source:
The Ecomonic Times
