·
Glucosamine and/or chondroitin sulfate: Systematic surveys of
smaller controlled trials led to a large multicenter trial that concluded that
these products are superior to placebo in improving performance and slowing the narrowing of the joint space in patients
with moderate to severely painful and disabling osteoarthritis of the knee. It
remains uncertain whether their use also slows degradation of joint cartilage.
·
Ginkgo biloba: Americans spent nearly $250 million on
this herbal product in 2000. The literature shows no evidence that it improves
cognition, but over 3000 older Americans currently participate in a randomized
blinded trial to ascertain whether its use can reduce
the rate of onset and progression of dementia.
·
Saw palmetto (Serenoa repens) and African plum
(Pygeum africanum):
Each of these botanicals has been advocated for aging men to obtain symptomatic
relief treatment of benign prostatic hyperplasia.
Sales of saw palmetto are growing, with an estimated $131 million spent on the
product consumed by Americans in 2000. However, clinical trials have shown that
saw palmetto is ineffective in this setting.
·
St.-John's-wort (Hypericum perforatum): Among the most popular herbal
products worldwide, numerous small studies and systematic reviews suggested it
to benefit patients with a wide range of depressive
syndromes. High-quality, randomized, placebo-controlled trials found
St.-John's-wort to not be superior to placebo for treatment
of major depression of moderate severity, a spectrum of illness that clearly
warrants professional evaluation and treatment.
·
Echinacea species:
Echinacea roots are widely used to treat or prevent
respiratory infections, with over $200 million in sales in 2000.
Although in vitro studies have shown that Echinacea constituents stimulate humoral and cellular immune responses, systematic reviews
of the clinical trials have not concluded that they are beneficial.