WHO monographs on selected medicinal plants - travolekar.ru

Cortex Salicis
Daily consumption of the extract with 240.0 mg salicin per day affected
platelet aggregation to a lesser extent than acetylsalicylate (27).
Chronic lower back pain
Standardized extracts of the bark exhibited analgesic effects similar to
those of higher doses of acetylsalicylic acid. A daily dose of 1572.0 mg of
an extract of the crude drug (standardized to 15.2% salicin or 240.0 mg
salicin per day) was superior to placebo in the treatment of pain in patients
with osteoarthritis of the hip and the knee, and in patients with
exacerbations of chronic low back pain. In two open studies, unspecified
extracts of the crude drug exhibited similar efficacy to the normal treatment
regime of nonsteroidal antirheumatic drugs and the efficacy was
similar to that of refecoxib (18).
A randomized placebo-controlled clinical study evaluated the efficacy
of a willow bark extract in 210 patients with chronic lower back pain. The
patients were assigned to receive an orally administered willow bark extract
with either 120.0 mg (low dose) or 240.0 mg (high dose) of salicin, or
a placebo, with tramadol as the sole rescue medication, in the 4-week trial.
The principal outcome measure was the proportion of patients who were
pain-free without tramadol for at least 5 days during the final week of the
study. A total of 191 patients completed the study. The number of painfree
patients in the last week of treatment was 27 (39%) of 65 in the group
receiving high-dose extract, 15 (21%) of 67 in the group receiving lowdose
extract, and 4 (6%) of 59 in the group treated with placebo (p < 0.001).
The response in the group treated with the high dose was evident after
only 1 week of treatment. Significantly more patients in the group receiving
the placebo required tramadol during each week of the study
(p < 0.001). One patient in the treatment group suffered a severe allergic
reaction (14).
An open, non-randomized study (postmarketing surveillance) assessed
the efficacy of an extract of the crude drug in three groups of patients aged
18–80 years presenting over an 18-month period with acute exacerbations
of low back pain. The first group of 115 patients was prescribed a daily
dose of the extract containing 120.0 mg of salicin. A second group of
112 patients was prescribed the extract equivalent to 240.0 mg salicin per
day. A third “control” or “comparator” group of 224 patients received
conventional therapy. In the patients who had received conventional therapy,
the exacerbations had been shorter but the pain was more intense as
judged by Arhus Index and Total Pain Index. After 4 weeks of treatment,
about 40% of patients in the group treated with the extract equivalent to
240 mg salicin per day were free of pain. In the group treated with extract
containing 120.0 mg of salicin, as a whole, about 19% of patients were
315