Vol.9: Not getting an erection in the morning is a warning signal of ED

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【Not getting an erection in the morning is a warning signal of ED】


Most men must have experience of “getting erection when waking up”. In fact, this “morning erection” can be an important factor to detect the initial-symptom of ED, as well as the type and severity of ED.
The terrestrial Mammalia repeats non-REM sleep (deep sleep) and REM sleep (comparatively shallow sleep) during sleeping. As for the healthy men, the phenomenon which is called “nocturnal penile tumescence” occurs during REM sleep. This erection phenomenon which occurs approximately 4-8 times is caused due to the seesaw relationship between two kinds of autonomic nerve systems (sympathetic and parasympathetic nerve). Because it is not an erection which occurs with sexual stimulation or excitement such as having sexual dreams, this “nocturnal penile tumescence” is even seen among babies during the time they are sleeping as well. “Getting an erection when waking up” is the last one of the “nocturnal penile tumescence” cycles before waking up.
It is known that loss of nocturnal penile tumescence is a warning sign of ED. This is because when you have weaker erections at the time of sexual intercourse, the erections which you get with nocturnal penile tumescence apt to become weaker. Conversely, if you are consistently getting hard erections at awakening, it can be evidence that you are still possible to get sufficient erections during sexual intercourse. Getting sufficient morning erections mean that there is no mechanical problem at least in the series of mechanisms involved in getting an erection. Also, because getting an erection when waking up hardly has anything to do with mental influences, it is suggestible that most of the cases where men who don’t get sufficient erection during sex, but can get a sufficient erection when waking up, are possibly disturbed by mental factors, and should be classified as ideogenetic ED.
On the other hand, in case of not only getting an erection when having sexual intercourse, but also not getting an erection at awakening, although there is still a possibility of ideogenetic ED, this it’s more likely to be organicus ED. And in the case of so-called organicus ED, which is caused by diabetes, arteriosclerosis, stenosis and thrombus blockade of the penile artery, penile surgery and injury, it is more likely to cause serious symptoms, that give more possibility that the ED curatives doesn’t work sufficiently.
In this way, nocturnal penile tumescence can not only be a tool to diagnose between ideogenetic ED and organicus ED, but also it be an indication to gauge the effect and dose of ED curatives. Also, as nocturnal penile tumescence usually declines prior to the subjective symptoms of ED, it’s useful for the early diagnosis of ED as a sign of decline in erection strength.
In this way, morning erection becomes a valuable key in the scene of ED treatment. Also, it plays a role like an alarm which warns of the signs of ED to the patients.
For anyone who thinks they are not getting an erection when waking up recently, or don’t remember the last time it happened, please be aware. If you are thinking about improving your condition by taking medication, don’t hesitate to visit our practice for consultation.


【Supervisor of this article】

Ken Takemori, MD. An anesthesiologist and Director of Shibuya 3rd Block Clinic.


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