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Erection self-test

Erection self-test

Overview

The nocturnal penile tumescence (NPT) stamp test is a test that confirms the inability to achieve and maintain an erection.

Review Date 10/13/2023

Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.