The use of anti-fever drugs such as aspirin
and acetaminophen may prolong influenza A and possibly other viral
infections, according to researchers at the University of Maryland
schools of medicine and pharmacy.
In a series of vaccine studies conducted between
1978 and 1987 at the University's Center for Vaccine Development:
- 54 volunteers were injected with Influenza
- 45 with S. sonnei
- 21 with R. rickettsii
During these studies, some of the subjects were
given aspirin or acetaminophen
(paracetamol) for relief of symptoms such as fever.
The current study compared the duration of illness
in those who received the medication with those who did not and
found that flu sufferers who took one of the anti-fever medications
were sick an average of 3.5 days longer
than people who did not take either of the drugs.
On average, flu symptoms lasted 5.3 days in
participants who did not take aspirin or acetaminophen, compared
with 8.8 days in people who took the anti-fever drugs.
"The analysis suggests that anti-fever
therapy prolonged illness in subjects infected with Influenza A,
but not shigellosis or Rocky Mountain spotted fever," says
Philip A. Mackowiak, MD, one of the study's principal investigators
and chief of the Medical Care Clinical Center, V.A. Maryland Health
Care System and professor at the School of Medicine.
"Our research suggests that fever may have
different roles in the resolution of bacterial and viral infections,"
says Karen I. Plaisance, PharmD, associate professor at the School
of Pharmacy, the study's other lead investigator.
In comments to Reuters Health, Dr. Plaisance
noted that similar findings have been reported in studies of chickenpox.
She also noted that the findings are based on
studies conducted in the past, but that they hope to conduct studies
in the future in which people with flu symptoms are randomly assigned
to receive anti-fever medication or an inactive placebo.
"The good news is that
anti-fever drugs make people feel better when they have infections.
The bad news is that they may cause the illness to linger longer,"
says Dr. Mackowiak, adding that people "should be aware that
anti-fever drugs have a modest
cost associated with relief and that cost is that they
may be sick longer."
December 2000; 20: 1417-1422