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Phosphodiesterase-5 Inhibitor Use: An Under-Reported Cause of Profuse Nasal Bleeding
Petros V Vlastarakos1, Thomas P Nikolopoulos2
1Ear, Nose, and Throat Department, MITERA Infirmary, Athens, Greece.
Background:
Phosphodiesterase-5 (PDE-5) inhibitors enhance penile erection and have gained popularity not only for erectile dysfunction, but also in recreational settings. Nevertheless, adverse effects have been associated with their use, with nasal bleeding among them. PDE-5 inhibitor action is materialized through the inhibition of the cyclic guanosine monophosphate (cGMP) enzyme. cGMP is present at several sites of the human body in addition to the corpus cavernosum, leading to the adverse effects associated with its nonselective inhibition.
Case Reports:
Two male patients with severe epistaxis who were taking PDE-5 inhibitors for erectile dysfunction or recreational purposes are discussed. Surgical intervention was required in both patients to control the nasal hemorrhage. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Nasal bleeding in patients who are taking PDE-5 inhibitors might represent an under-reported cause of epistaxis because of the unwillingness of most male patients to discuss issues pertaining their use without hesitation. Yet such episodes are rather profuse. This is especially true when the venous engorgement caused in the nasal mucosa by the smooth muscle relaxant effect of PDE-5 inhibitors is combined with a second event (e.g., specific drugs or blood dyscrasia). Emergency physicians should be also aware of the possibility that in the coming years the number of such cases might increase because of the increased use of these medications for erectile dysfunction or recreational purposes. It is likely that these patients could not be managed conservatively, but would rather require referral to an Ear, Nose, and Throat Department for surgical intervention.
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