In HIV-infected patients, marijuana has
been used as an appetite stimulant and as a treatment for the nausea
associated with some antiretroviral agents. However, concern has been
raised that such therapy could have a harmful effect on disease status,
because in theory,
cannabinoid use could increase HIV levels by
impairing the immune response or by interfering with the activity of
protease inhibitors. Previously it was shown that short-term
marijuana use did not influence nelfinavir metabolism. Although
marijuana use did produce a drop in indinavir levels, this fall was
small and unlikely to be clinically meaningful. However, it still
remained unclear whether cannabinoid use had an effect on viral load or
CD+ cell counts. To investigate, Dr. Donald I. Abrams, from
the University of California at San Francisco, and colleagues assessed
the outcomes of 67 HIV-infected patients who were randomly assigned to
use marijuana cigarettes, cannabinoid capsules, or sugar pills
(placebo) three times daily for 21 days. All of the patients had been
receiving the same antiretroviral regimen, which included indinavir or
nelfinavir, for at least 8 weeks before the study began. More than half of the subjects in each
group had undetectable viral loads throughout the study, the
researchers note. Although not statistically significant, marijuana and
cannabinoid use were actually associated with a slight drop in viral
load compared with placebo use. Marijuana and cannabinoid use did not
produce a drop in CD4+ or CD8+ cell counts. In fact, compared with
placebo use, treatment with these agents was actually associated with a
slight increase in cell counts. The results suggest that short-term
cannabinoid use is not unsafe for patients with HIV
infection, the
authors note. "Further studies investigating the therapeutic potential
of marijuana and other cannabinoids in patients with HIV infection and
other populations are ongoing and should provide additional safety
information over longer exposure periods," they write.