Copyright 2000 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.
To the Editor: The vasodilatory properties of sildenafil (Viagra) are well established and many of sildenafil's adverse effects (headache, flushing, dyspepsia, dizziness) result from vasodilation. Sildenafil-related myocardial infarction and sudden death also may be related to its vasodilatory effects.
Sildenafil alone has been associated with episodes of hypotension and the concomitant use of sildenafil and nitrate vasodilators is contraindicated because of hypotensive crises. Thus, there is some question whether the use of sildenafil in patients taking nonnitrate antihypertensive drugs might present an increased risk. Certainly, many antihypertensive drugs alone cause vasodilation and hypotension. According to the package insert, "Controlled studies of drug interactions between Viagra and other antihypertensive medications [except amlodipine] have not been performed."1 It would be helpful for clinicians to know the results of a study involving sildenafil and, for example, doxazosin mesylate or terazosin hydrochloride, which are well known to cause hypotensive reactions in some patients.
To determine whether current data might indicate an increased risk among patients taking sildenafil in combination with nonnitrate antihypertensives, I requested, in December 1998, the case reports of sildenafil-related adverse drug reactions (ADRs) that had been submitted to the US Food and Drug Administration (FDA). I received the list of ADR reports from April to June 28, 1998.2 The list contained 439 ADRs. Of these, 127 (29%) occurred in patients taking antihypertensive drugs. Twenty of these cases involved nitrates. Removing these cases, 107 (25.5%) of the remaining 419 reports involved other antihypertensive drugs. However, the FDA list contained many apparent redundancies and often lacked key information such as patients' ages or details of adverse events. Removing the redundancies, 360 cases remained. Of these, 87 patients (24.2%) were taking nonnitrate antihypertensive drugs.
Thus, overall, about 24% of sildenafil-related ADRs reported to the FDA from April 22, through June 28, 1998 occurred in patients taking nonnitrate antihypertensive drugs. This percentage exceeds the approximately 13% of American adults receiving treatment for hypertension,3 but it is less than the 33% of subjects taking antihypertensives in the placebo-controlled sildenafil trials.4 Whether the fact that nearly one quarter of sildenafil reports to the FDA also involved antihypertensive drugs indicates an increased risk factor, a reporting bias, a statistical error secondary to incomplete information in the FDA reports, or a reflection of an older and less healthy patient population taking sildenafil is not known.
Physicians should be aware of the possibility of hypotensive reactions in patients taking antihypertensive drugs and sildenafil and should alert patients about this potential adverse effect.5
Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature
Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal
Instructions
Comments are moderated and will appear on the site at the discretion of the Journal of American Medical Association editors. Comments should not exceed 500 words of text and 10 references.
Do not submit personal medical questions or information that could identify a specific patient, questions about a particular case, or general inquiries to an author. Only content that has not been published, posted, or submitted elsewhere should be submitted. By submitting this Comment, you and any coauthors transfer copyright to the journal if your Comment is posted.
* = Required Field
Disclosure of Any Conflicts of Interest* Indicate all relevant conflicts of interest of each author below, including all relevant financial interests, activities, and relationships within the past 3 years including, but not limited to, employment, affiliation, grants or funding, consultancies, honoraria or payment, speakers’ bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued. If all authors have none, check "No potential conflicts or relevant financial interests" in the box below. Please also indicate any funding received in support of this work. The information will be posted with your response.
Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more
Subscribe for full-text access to content from 1998 forward and a host of useful features
Activate your current subscription (AMA members and current subscribers)
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Customize your page view by dragging & repositioning the boxes below.
and access these and other features:
Register Now
Enter your username and email address. We'll send you a reminder to the email address on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.