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Understanding Erectile Function Causes and Solutions for Not Waking Up with Erection

Written by

Science & Humans

Medically approved by

Maria Jacob

Last updated

Monday, September 26, 2022


Not waking up with an erection? Don’t panic. While yes, this could be a sign of erectile dysfunction (ED) or low testosterone, it does not mean that you did not experience an erection during the night before. Nocturnal penile tumescence (NPT) is the scientific term that describes the phenomenon that is nocturnal erections, but many men have named this “morning wood,” because of the experience of having an erection when they first wake up [1]. Indeed, males of all ages typically have 3-5 erections per night. As people age, they may naturally notice less nocturnal erections for a variety of reasons:

Your erection could disappear by the time you wake up

In this case, you are still experiencing nightly erections, even if you don’t have one in the morning. To understand why this is happening, it is important to understand why nocturnal erections occur. While the exact reason for nocturnal erections is not fully understood, it seems that they rely heavily on rapid eye movement (REM) sleep, which is the deep-sleep when dreams often occur [2]. Similarly, some authors suggest that during REM sleep, the parts of the brain that constantly inhibit (or stop) erections from happening effectively relax, allowing an erection to occur [3]. A lack of quality REM sleep then, could explain why a nocturnal erection did not occur during a particular night.

Therefore, a nocturnal erection can be a tell-tale sign of whether erectile dysfunction is occurring, and whether it is because of psychogenic (psychological) or physiological (body-related) reasons. An NPT-test can be conducted in a sleep lab to assess whether nocturnal erections are occurring; if so, your clinician may have a better reason to rule out physiological erectile dysfunction, and suggest that your ED is psychological [1]. Caution should be taken though, as this test has its limitations, and a health-care provider can provide context to its results [4].

What if I do have erectile dysfunction?

A lack of nocturnal erections could be explained by erectile dysfunction [5]. There are many physiological reasons for erectile dysfunction, ranging from spinal cord injury to an age-related drop in testosterone and blood-flow to your penis [5]. However, medications are available, including sildenafil and tadalafil, that improve blood-flow into an erection and are the recommended first-line medical treatment to treat a variety of physiological ED [6]. These treatments are available here through scienceandhumans.com, and use has been associated with an increase in nighttime erections [7].

What if my ED is psychological?

Not to worry – while ED can be explained by a variety of physiological reasons, psychological ED is also easily treatable. Guidelines recommend that patients work with their health care providers to make a shared decision of whether sildenafil or another ED medication is appropriate for them [6]. Similarly, a sex therapist can help distinguish some of the thinking patterns that may be leading to your ED; we offer this service through scienceandhumans.com. Notably, ED medications work safely for ED related to antidepressant use [8].

If you are concerned about a sudden loss of nighttime erections, you should speak to your primary care health practitioner. You can also consult one of our medical practitioners for more information on sildenafil and other available treatments of ED. To read more on erectile dysfunction or other sexual dysfunction, visit scienceandhumans.com. 


1. International Society for Sexual Medicine. What is the nocturnal penile tumescence (NPT) test? n.d. Septemeber 17th, 2022]; Available from: https://www.issm.info/sexual-health-qa/what-is-the-nocturnal-penile-tumescence-npt-test

2. Schmidt, M.H. and H.S. Schmidt, Sleep-related erections: neural mechanisms and clinical significance. Current Neurology and Neuroscience Reports, 2004. 4(2): p. 170-178.

3. Bancroft, J., The endocrinology of sexual arousal. Journal of endocrinology, 2005. 186(3): p. 411-427

4. Zou, Z., et al., The role of nocturnal penile tumescence and rigidity (NPTR) monitoring in the diagnosis of psychogenic erectile dysfunction: a review. Sexual medicine reviews, 2019. 7(3): p. 442-454

5. Suh, D.D., C.C. Yang, and D.E. Clowers, Nocturnal penile tumescence and effects of complete spinal cord injury: possible physiologic mechanisms. Urology, 2003. 61(1): p. 184-189.

6. Hatzimouratidis, K., et al., Guidelines on male sexual dysfunction: erectile dysfunction and premature ejaculation. European urology, 2010. 57(5): p. 804-814.

7. Elhanbly, S.M., et al., Nocturnal penile erections: A retrospective study of the role of RigiScan in predicting the response to sildenafil in erectile dysfunction patients. Journal of advanced research, 2018. 14: p. 93-96.

8. Taylor, M.J., et al., Strategies for managing sexual dysfunction induced by antidepressant medication. Cochrane Database of Systematic Reviews, 2013(5).


Further reading

Understanding the Fundamentals of Erectile Dysfunction

Understanding the Fundamentals of Erectile Dysfunction

An erection is the result of increased blood flow into your penis. Blood flow is usually stimulated by either sexual thoughts or direct contact with your penis.

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5 Myths of Erectile Dysfunction – Debunked

5 Myths of Erectile Dysfunction – Debunked

In Canada, erectile dysfunction (ED) is a common problem that affects millions of men, despite myths about it being psychological, exclusively affecting older men, and in ...

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Can Testosterone Replacement Therapy Help with ED ?

Can Testosterone Replacement Therapy Help with ED ?

Low levels of testosterone and poor blood flow to the penis can contribute to erectile dysfunction (ED). TRT and PDE5 inhibitors can be taken with him to improve outcomes ...

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