Limp Results From Penile 'Stress Test'
NEW YORK (Reuters) -- Tests on the impotence drug alprostadil reveal that use of the medication increases penile blood
flow, but may not result in firm and lasting erections.
"There was an increase in (penile) volume, up to 114%," say researchers at the Centre for Impotence and Fertility in Rome,
Italy, "but not many (erections) had a real and lasting hardness."
Their report appears in this week's issue of the British journal The Lancet.
Alprostadil is administered in the form of a small pellet which, inserted into the urethra, can stimulate blood flow within
erectile tissue. A 1996 study of 1,511 impotent men, published in The New England Journal of Medicine, found that nearly two
thirds of men using the drug achieved scores of 4 ('erection sufficient for intercourse') and 5 ('rigid erection') on the standard
5-point Erection Assessment Scale (EAS). Sixty-five percent of those men went on to report successful intercourse occurring
at least once during a three-month period of using the drug, compared with just 19% of those on placebo.
The new Italian research focused on 123 impotent men, most of whom had already tried anti-impotence therapies involving
the injection of medications directly into the penis.
The investigators say special scanning devices detected immediate increases in penile blood flow (and penile volume) in all 123
men after insertion of alprostadil into the urethra.
However, instead of using the EAS to measure erectile strength, the researchers chose what they considered to be a more
"objective method." Erections were judged to be "positive" only "when a downward... strength of 1 kilogram did not buckle the
penis." To test for such 'buckling,' they dangled 1 kilogram (approximately a half pound) weights from each erect penis.
A special pressure-monitor was wrapped around erections to test for radial rigidity as well.
The result? "Complete rigidity" was obtained by just 11 of the 123 study subjects, and a "full and not a lasting erection (1 to 2
minutes)" was achieved by only 16.
"There seems to be no correlation between volume increase and hardness," the authors conclude.
They say most of the men in the study seemed less than pleased with alprostadil's overall effectiveness -- "five patients wished
to try the system at home, two of them got good results, the rest wished to stay on... (penile) injections." SOURCE: The Lancet
(1997;350:1682) |
