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Healthy Volunteer Study of Sildenafil Effects Upon Vision

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00251784
Recruitment Status : Completed
First Posted : November 10, 2005
Last Update Posted : November 10, 2005
Information provided by:
University of Cambridge

Brief Summary:
Patients sometimes report subjective visual effects when taking sildenafil. Our study set out to measure these in a controlled setting. Subjects were asked to detect patterns presented on a monitor screen.

Condition or disease Intervention/treatment Phase
Blindness Drug: Sildenafil Phase 4

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Study Type : Interventional  (Clinical Trial)
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double
Primary Purpose: Educational/Counseling/Training
Official Title: A Double-Blind, Randomised, Placebo Controlled Healthy Volunteer Study to Investigate the Nature and Origin of the Disturbance of Vision Induced by Single Oral Doses of Sildenafil
Study Start Date : February 2002
Study Completion Date : June 2003

Resource links provided by the National Library of Medicine

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria: male -

Exclusion Criteria:


Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00251784

Sponsors and Collaborators
University of Cambridge
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Principal Investigator: Morris J Brown, MD University of Cambridge
Study Director: John Mollon, FRS University of Cambridge
Layout table for additonal information Identifier: NCT00251784    
Other Study ID Numbers: LREC 98/297
First Posted: November 10, 2005    Key Record Dates
Last Update Posted: November 10, 2005
Last Verified: December 2003
Additional relevant MeSH terms:
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Vision Disorders
Sensation Disorders
Neurologic Manifestations
Nervous System Diseases
Eye Diseases
Sildenafil Citrate
Vasodilator Agents
Phosphodiesterase 5 Inhibitors
Phosphodiesterase Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Urological Agents