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Erectile Dysfunction
considerable confusion, with various publications on L-arginine in should be minimal compared with the potency of warfarin, but
cancer patients with contradictory findings. caution is advised.
However, men who have suffered a myocardial infarction should The safety of supplementing with Prelox and co-medicating with
definitely refrain from taking Prelox because L-arginine may pose a PDE5 inhibitors needs to be addressed as a potential synergistic
health risk to them.
29
One study investigated supplementation with effect may also generate advanced side effects. Limited knowledge is
accelerating dosages of L-arginine, from 3 to 9g daily, for improving available on the simultaneous use of Prelox and PDE5 inhibitors. An
vascular stiffness and heart ejection fraction in addition to standard exploratory investigation tested co-medication in men >50 years of
post-infarction therapy. The study was prematurely terminated after age presenting with moderate to severe ED who took four Prelox
six months because of safety concerns, as six patients (8.6%) taking tablets a day and 50mg Viagra
®
twice a month 30 minutes prior to
L-arginine died, whereas none in the placebo group did. Interestingly, intercourse (Margus Punab, Tartu Men’s Clinic Finland; personal
after six months the L-arginine plasma levels were not significantly communication). The results were judged ‘good’ and, more
different between the treatment and placebo groups. The authors importantly, no side effects were reported with the combination.
state “the excess mortality was an unexpected safety monitoring
concern and the results could be due to (small but nonzero) chance”. Conclusion
Schulman et al. conclude that L-arginine therapy should not be given Prelox is a safe, well-tolerated and efficacious treatment for mild to
to patients following myocardial infarction. moderate aetiologies of ED. Its efficacy has been proved in four
clinical trials. The unique characteristic of Prelox is the restoration of
Prelox has not been systematically investigated for specific drug men’s ability to spontaneously respond to sexual arousal. Prelox is a
interactions. From the pharmacological activities of Prelox it may be treatment option for ageing men who discover the first signs of
concluded that for certain medications the attention of the treating decreasing erectile quality. Studies show that men taking Prelox are
physician is mandatory. Men diagnosed with angina pectoris on more confident and more frequently have intercourse. This is a
medication with ‘nitrates’ (i.e. glycerol nitrate, isosorbide dinitrate, protective measure for developing ED, as found in an epidemiological
isosorbide mononitrate) should supplement with Prelox only with the study. Men who have intercourse more frequently are less likely to
consent of their physician. develop ED later in life.
30
n
Prelox was shown in two trials to lower blood pressure, although not
Steven Lamm is a Clinical Assistant Professor of
to the point of hypotension.
14,20
Therefore, caution should be
Medicine at New York University School of Medicine. He
exercised in men medicating with antihypertensive medications. The is a clinical researcher in the area of sexual medicine
guidance of a physician is advised as the hypertensive medication
and the author of two books: The Virility Solution and
The Hardness Factor. Dr Lamm is Chairman of the
dosage might require adjustment. Men taking oral anticoagulants
Men’s Health platform for the Revolution Health Group,
such as warfarin should supplement with Prelox only under the an Internet consumer site on sexual health issues.
supervision of a physician, as the improved endothelial function and
nitric oxide synthesis naturally lower platelet activity. The latter effect
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