Nocturnal penile tumescence

Covers nocturnal penile tumescence (nighttime erections), what it can indicate about erectile function, vascular health, and hormone status, and how it’s assessed in a clinical setting. This topic matters because changes in NPT can help differentiate physical vs. psychological causes of ED and guide next-step testing and treatment.

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The essentials for nocturnal penile tumescence — then explore the latest posts below.

Why no morning wood happens and what it reveals about your vascular health

Why no morning wood happens and what it reveals about your vascular health

Dr. Alexander Grant, MD, PhD avatar
Dr. Alexander Grant, MD, PhD: Urologist & Men's Health Advocate
Dec 01, 2025 · 14 min read

Losing morning erections for many weeks often means nocturnal penile tumescence is being blunted by reduced penile blood flow, impaired nerve signaling, or poor sleep — and it can flag vascular problems even when testosterone is normal. Here’s how to interpret the change and when it should prompt a closer look at diabetes and cardiovascular ...

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