Non-Sexual Erections

Erections don’t occur only during sexual stimulation.  On this page we will discuss three main reasons men get non-sexual erections.  These include nocturnal/morning erections, random/unwanted daytime erections, and a medical disorder called priapism.


Nocturnal erections or nocturnal penile tumescence (NPT) are erections that are triggered unconsciously while a man is sleeping.  These erections are not usually caused by mental or physical stimulation.  Instead they are triggered mostly by testosterone and the central nervous system while a man is asleep.[i]  In fact, the presence of nocturnal erections is a good indicator that testosterone levels are within normal range.

The purpose of nocturnal erections is to provide oxygen to the tissues of the penis.  Having these tissues healthy allows for on-demand erections when the man is awake and desires to engage in sexual activity.  However, because nocturnal erections occur regularly each night, it is completely unnecessary for men to have regular erections while awake in order to provide oxygen to the tissues. In fact, men who masturbate frequently can actually have a decrease in nocturnal erections and develop future difficulties getting or keeping erections.[ii]  In addition, men who have pornography and masturbation addiction often engage in excessive mental and physical stimulation and lose the ability to have nocturnal erections (or at the very least have fewer, less rigid nocturnal erections).  This can likewise decrease the ability to have on-demand erections and is one reason why men with pornography/masturbation addiction often suffer from erectile dysfunction.   

Nocturnal erections are triggered during the REM cycles of sleep.  The REM or rapid eye movement phase of sleep is when men dream.  Not all dreams are erotic or sexual.  Men will go through 2-6 REM cycles each night (average is 4-5 REM cycles).  During most of these cycles he will get an erection.  Each erection will last anywhere from 30-45 minutes, so on average men will spend 2 ½ to 3 hours each night with an erection.   These erections may be most noticeable during the early morning hours, right as a man wakes up.  This has given rise to the slang term for of “morning wood” for a morning erection. 

There are two mechanisms that are widely accepted as causing nocturnal erections.  The first is that the central nervous system triggers these erections in a different part of the brain from areas that cause mental stimulation.  As a review, the penis is in a state of “contraction” when it is flaccid in order to prevent blood filling and engorging the erectile tissues and causing an erection.  This contraction is largely caused by a neurotransmitter called norepinephrine.  During REM the brain switches off certain cells that release norepinephrine as the body “relaxes” and goes into the rest state.  When the norepinephrine is switched off, the blood vessels in the penis relax thus allowing a spontaneous erection to occur.  Testosterone plays an important role in nocturnal erections as well.  It is well documented that men with higher testosterone levels will have stronger, more rigid nocturnal erections.  While men with lower testosterone levels will have weaker, more limp erections, or no nocturnal erections at all.  This is opposite from mentally and physically stimulated erections which are not necessarily dependent on testosterone levels (a man can get erections through mental or physical stimulation even if his testosterone levels are low).  Higher testosterone levels tend to allow the norepinephrine switch to be turned more completely “off” while lower testosterone levels lead to incomplete switching off of norepinephrine resulting in less rigidity during a nocturnal erection.[iii]


Even though nocturnal erections are almost entirely caused by the central nervous system, there can also be components of psychogenic (mental) and reflexogenic (physical) stimulation.  For example, random sexual dreams during some REM cycles may intensify or promote further erection of the penis via mental stimulation.  Reflexogenic stimulation may also occur if the penis rubs against the mattress or bedding or due to any pressure or sliding of the penis against the underwear.  In addition, the nerves that recognize the fullness of the bladder are found in the pelvic plexus and thus a full bladder (especially in the morning) can physically stimulate an erection.  This may be a reason why men experience erections when awaking up in the mornings, even if they may not be in the middle of a REM cycle and dreaming.


Some men actually don’t want to have nocturnal erections and wonder what they can do to stop having them.  Since nocturnal erections are actually healthy for the male reproductive system, trying to stop them is not a good idea.  Oftentimes the reason men desire to have less nocturnal erections is due to some of the difficulties they may experience during the night or upon waking.


One of the most common complaints men have about nocturnal erections is that they often have to wake up to adjust themselves when an erection becomes uncomfortable.  This can be due to the penis becoming trapped in the band of the underwear.  This occurs more often in men who wear low-riding underwear or in men who may have a penis that is longer than average.  In these cases, having a pair of underwear to sleep in that has a higher waistband or a more flexible waistband can often be helpful.  Likewise, men who wear underwear that is too tight or form fitting can prevent erections from pointing somewhat forward.  This can press the penis completely against the abdomen which may be uncomfortable in some men, especially if the muscles at the root of the penis push the penis outward against the underwear.  This can be solved by wearing looser fitting underwear, or underwear that has an athletic pocket in the front that allows forward movement of the erect penis.  Discomfort can also occur if the erection slips out of the underwear, most often through the front flap.  This can cause the penis to become overly stimulated as it rubs against bedding or pajama fabric.  The most simply remedy is to simply adjust the penis back into the underwear upon waking.  However, men who repeatedly have issues with erections slipping out of their underwear may find that changing underwear to something that doesn’t have a flap can be helpful.  For those who like a front flap, there are different types of underwear with front flaps that can prevent this problem – these include flaps that are fully covered on the inside of the underwear or an H flap in the front.

Another issue some men often complain about is waking up with an erection that might be visible to someone else if they got out of bed.  Typically this isn’t a concern in men who sleep with their sexual partner, but can be an issue in men who have a roommate.  Most often, nocturnal erections subside upon waking up and usually go away within a minute or so.  Men in these situations often find that lying on the side, reading, or simply distracting the mind for a minute often allows an erection to subside to the point that it isn’t noticeable.  Wearing baggy shorts to bed can also help hide an erection or semi-erect penis as well.  For some men, nocturnal erections can be strengthened by the sensation to urinate in the morning and may not completely go away until after urination has occurred.  In these cases, men often find going to the restroom and urinating can help morning erections subside.


The only time men should seek treatment about nocturnal erections is if they don’t have them at all.  Men who don’t experience nocturnal erections are often at a much higher risk of experiencing erectile dysfunction.  Men should feel comfortable bringing up a lack of nocturnal erections to a healthcare provider.  This may actually prompt them to ask more questions or order blood tests to ensure that testosterone levels are within normal range.      




Most men have experienced getting at erection when there was no sexual stimulation or in situations where he definitely doesn’t want to have one.  Since getting an erection is a reflex rather than completely conscious decision, erections can occur at random or inconvenient times and getting an erection to go away isn't always "easy".  This is more common during the teen years as testosterone levels are at their highest, but it also occurs in adult men from time to time.  This can lead to discomfort or embarrassment if the penis gets trapped or bulges underneath clothing. 

There are multiple reasons why men may get a not sexual erection.  Common causes include:

  • Penis getting brushed against underclothing while walking or during physical activity

  • Penis getting caught in an uncomfortable position in the clothing

  • Being relaxed

  • Surges of testosterone

  • Anxiety – fear of getting an erection in a certain situation actually causes an erection

  • No reason at all whatsoever

First, it’s important to recognize that random erections typically don’t indicate any issues or problems.  In fact, they are a good indication that a man’s reproductive system is healthy.  However, sometimes these random erections occur at times where erections are not wanted.  This may create embarrassing situations for a man if they occur during a shower at the gym (most high school boy’s worst nightmare) or when it bulges under the clothing and may be noticeable to others.  Typically, just stopping and taking a few breaths often can help an unwanted erection go away.  However, here are some tips that men have found helpful:[iv]

  • Distracted thinking – thinking about something else, counting, basically taking the mind off the erection often helps.

  • Covering the crotch – simply placing something like a book, backpack, or blanket over the crotch area can help (one reason why lots of men use those airplane blankets when they take a nap…good way to hid nocturnal erections during sleep).  Another option when sitting is to pull the bottom of a shirt over the pelvic area to hide an erection until it goes away on its own.

  • Adjusting the penis – oftentimes an erection begins, but when it becomes trapped in certain positions it can become painful or stimulating which only prolongs the erection.  Many men find putting their hands in their pockets and adjusting the penis to an upright position against the lower abs usually eliminates discomfort and stimulation

  • Put your hands in your pockets – hands in the pockets push the crotch area shorts/pants out thus hiding the bulge from an unwanted erection.

  • Simply ignoring it – if it isn’t painful or noticeable, oftentimes just ignoring it and getting on with whatever he's doing is an option.

  • Don’t worry about it and let it take its course – anxiety about having a random erection is perhaps one of the worst things a guy can do (easier said than done for some).  In some men, the fear of getting an erection in certain situations inevitably leads to him getting an erection. 

As a medical professional that deals in men’s health, we’re always taught to be aware that men can get erections during pelvic or rectal examinations.  Most medical professionals would not think anything of someone getting an erection in an exam room situation.  In almost all cases, the medical profession will suspend an examination to give the man his privacy.  In no way should the fear of getting a random erection during a provider visit keep men from seeing their medical provider about men’s health issues.  If it occurs, it's a total non-issue for medical professionals.

However, for men who find that they are getting random erections with high frequency (multiple times a day), it may be a good idea to talk to a health care provider.  In some cases, men with prostate infections or anxiety disorders have frequent, random erections as one of the symptoms.  In the case of prostatitis, treating the prostatitis can decrease the frequency of random/unwanted erections.




Priapism is defined as an unwanted erection that will NOT go away – even after ejaculation.  If an erection lasts for more than four hours, severe damage to the erectile tissues may occur due to clots and stagnant blood.  Priapism is a medical emergency and requires immediate medical attention!  Priapism is typically not caused by sexual stimulation and is often not sexually stimulating.  In fact, ejaculation during priapism will usually not make the erection go away.  Priapism can be caused by blood disorders like sickle-cell anemia and leukemia or an injury to the penis or groin area that can disrupt the normal blood flow and nerve signals from the erectile centers.  However, one of the main causes of priapism can be certain medications.  The most common medications that can cause priapism are those medications used to treat erectile dysfunction.  However, other medications, especially those that affect the central nervous system like trazodone, some antipsychotics, and even alcohol, can cause priapism.  In addition, sometimes scorpion and black widow bites can induce priapism in men as well. 


There are two main types of priapism – ischemic (or “low flow”) and non-ischemic (or “high flow”).  These two types of priapism have different types of symptoms.


Ischemic (Low-Flow) Priapism

Ischimic or low-flow priapism is caused when blood cannot leave the penis.  It is typically painful and the erection may “stutter” or go between different erection stages on and off without going completely away.  The shaft of the penis is typically rigid; however, the glans (tip) is usually flaccid.  This type of priapism must be treated by a clinician urgently.  Injections of medication that can dilate the blood vessels or even using a needle and syringe to withdraw blood out of the penis may be necessary (to see a medical illustration of the blood withdrawal procedure, click HERE).  In some cases, surgery is required. 


Non-Ischemic Priapism

Non-ischemic or high-flow priapism is caused by too much blood flowing into the penis.  This is usually painless.  The shaft will be erect, but not rigid.  This is often the result of an injury to the perineum (area behind the scrotum) or injury to the genitals.  Icing the penis can often be helpful and allow the priapism to go away; however, if the erection goes on for more than four hours, tissue damage may occur.  If icing doesn’t help the priapism go away in the first hour or so, then it’s a good idea to get to an urgent care or emergency room for treatment.

Not treating priapism can cause death of the erectile tissues or damage due to blood clots that form in the erectile columns.  This damage can lead to permanent damage to the erectile tissues causing future erectile dysfunction.  It is always important to be seen by a doctor for an erection that won’t go away, no matter how embarrassing you think it may be to be seen for this condition.


[i] Testosterone and sleep-related erections: an overview -



[iv] (8/17/19)