Why Can't I Get a Full Erection? List of Potential Causes

Kristin Hall, FNP

Medically reviewed by Kristin Hall, FNP

Written by Our Editorial Team

Last updated 1/22/2021

We’ve all had it happen: a late night or early morning, the opportunity for some intimacy presents itself. Things seem like they’re going to happen, but like the first few attempts by the Wright brothers, it doesn’t quite get off the ground. 

Maybe you get farther along, things start to happen, but try as you might you just can’t seem to get to full mast, leaving you and your partner self conscious and shrugging. 

Failure to achieve full erection is a common problem, and the severity of the erectile dysfunction issue nationally to the point that 18 million men in the United States are suffering the symptoms of erectile dysfunction. 

We know. Erectile dysfunction is a scary term, which is why so many guys avoid addressing the problem. You may not be sure you even have erectile dysfunction. And if your problems are rare, uncommon or usually the result of alcohol or drugs, you may not even have it. 

How Erections Work

Erections are the result of two primary functions: increased bloodflow to the penis’s blood vessels, and the trapping of that blood in the penis by the tunica albuginea.

Inside the penis, there are two long chambers called the corpora cavernosa. The corpora cavernosa contains a lot of cardiovascular mechanics, including blood vessels and tissues, as well as one major artery each.

When you become aroused, your brain dilates the blood vessels, allowing blood to flow in. The blood becomes trapped in the corpora cavernosa, keeping you erect. 

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What’s Going Wrong

That’s how it’s supposed to work, anyway, but it’s not always the case. 

One form of ED — arteriogenic ED — is caused by inefficient arteries, which can reduce oxygen tension, leaving the muscles that typically keep the penis filled with blood a little weak and leaky. If blood flow is insufficient or it isn’t sealed inside, that causes erectile dysfunction.

But depression, and low self esteem can have the same effect on your ability to get hard, in large part due to the effects of stress and anxiety.

Whether physiological or psychological, partial erections are a warning sign for erectile dysfunction, and while they’re not as severe as complete lack of firmness, they represent a problem that should be tackled before it gets any worse. 

Erections fail to attain full size for a variety of physiological reasons, including chronic inflammation associated with diabetes, high blood pressure, metabolic syndrome, cardiovascular and neurological diseases, multiple sclerosis and Parkinson’s.

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Why You’re Not Getting All the Way Hard

Erectile dysfunction’s mechanism is quite simple, but the underlying cause could be a myriad of reasons, from poor diet and exercise habits, diabetes or heart disease, to low self-esteem, depression or anxiety. 

If you’re experiencing partial erections or unable to maintain a full erection, you’re likely suffering from one or more of these conditions. 

And there are more possible culprits for your relative softness. Your porn habit can even be responsible.

Other Symptoms of Erectile Dysfunction

Since ED is a urologic disease, one of the best resources is The National Institute of Diabetes and Digestive and Kidney Diseases. They share a thorough list of dysfunction symptoms that could suggest erectile dysfunction.

Difficulty getting an erection. The inability to get hard in sexual situations can leave a lot of men feeling self conscious. It can manifest due to physical and psychological causes.

Difficulty maintaining an erection. The inability to stay hard during sex and to orgasm is a major symptom of erectile dysfunction, and can also be be psychological or physiological.

Loss of interest in sexual activity. The loss of interest in sexual activity and general avoiding of sexual opportunity can be signs of either hormone imbalance or performance anxiety, both of which can cause problems in the bedroom and in relationships if left unaddressed.

If you’ve experienced any of these symptoms recently or frequently in the past, they may be further signs that you’re struggling with erectile dysfunction.

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What to Do If You Can’t Get a Full Erection

By now you probably have a good idea of whether or not you might be suffering from ED, but if you’re still not sure, it’s a good idea to be proactive in speaking to a medical professional. 

If you’re unable to get or maintain a full erection regularly, you may be suffering from erectile dysfunction, and it’s time to talk to a healthcare provider. 

A healthcare provider will check your blood pressure, see if you may be experiencing side effects from medications for hypertension or from antidepressants, and may also check your testosterone levels and examine you for prostate cancer, as these can all be factors in reduced erectile firmness.

The good news is ED is very treatable, with a variety of treatment options available. Everything from diet and exercise, to medications, and a more healthy lifestyle can help you regain firmness, and there are also prescription options available (like Viagra, generic Viagra, Cialis, Stendra) to help you obtain a firmer erection.

But don’t assume the cause is physical. Low self esteem and performance anxiety can cause ED, and those should be treated with the help of a therapist. There are various psychological treatments and approaches to dealing with the ED problem. Learn more here.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.