What Does ED Mean? Erectile Dysfunction Explained

Erectile dysfunction (ED) is when you can’t obtain or sustain erections during sexual intercourse. Issues with any part of the erectile response can cause ED. While people think it mainly affects older people, it’s also not uncommon in younger adults. 

People may be reluctant to discuss the problem with their doctor because they find it embarrassing. A 2014 analysis¹ of over six million men with ED discovered that only a quarter of them (25.4%) sought treatment for the condition. 

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What causes an erection?

Physical touch can cause an erection, which is the reflex response. Touch activates the parasympathetic nervous system (PNS). 

Emotion can also drive erections, and this is the psychogenic response. Specific pathways in the brain, including the limbic pathway, cause this response. 

The penis has two major muscle types. Centrally, you have the corpus spongiosum surrounding the urethra. Laterally, you have two corpora cavernosa which contain the erectile tissue. 

Sexual stimulation activates the PNS to release a series of chemicals like acetylcholine and nitric oxide. This relaxes the erectile tissue and allows more blood to enter the arteries of the penis, resulting in an erection. 

Another critical step for your body to maintain an erection is to decrease the rate at which the blood leaves the penis. The arteries push against the veins to compress them, creating a physical barrier. 

During this process, another chemical called phosphodiesterase 5 (PDE5) acts to revert the penis to its flaccid state.

Symptoms of ED

The primary complaint of ED is being unable to get a firm erection for sexual activities. There is also a psychological component to the condition. Many people with ED deal with emasculation, isolation, depression, and performance anxiety. 

These feelings could also extend into your social interactions. One study² highlighted emasculation with a quote: 

Outwardly, it always seemed that I was one of the lads and that I was okay... but inside... I didn't feel that I was matching up to them... I just felt that I wasn't as good as them, basically.’ 

Those with ED may also experience some level of insecurity within their romantic relationships. One study reported that 29% of participants felt that ED affected their relationships; 21% said their relationship ended as a result. 

Causes of ED

Causes of ED are often multidimensional, and there are two categories: Organic and non-organic causes. Organic refers to specific changes in the body's anatomy, whereas non-organic relates to psychogenic causes. ED was previously thought to be largely non-organic, but recent research found that 90%³ is organic. 

Organic causes can include issues with the blood supply or hormones:

  • Reduced blood flow to the penis is known as arterial insufficiency.

  • Too much blood escaping is venous leak syndrome.

  • Heart disease, diabetes, and hypertension can contribute to ED. 

Symptoms of organic ED tend to have slower progression and poorer outcomes. 

Hypogonadism⁴ is a rarer cause of ED, characterized by low testosterone levels. As men age, testosterone levels decrease. 

Non-organic refers to psychological factors. Episodes of ED tend to be more unpredictable, sudden onset, and situation-dependent. For example, you might feel anxious about performing in bed, resulting in an inability to obtain an erection. 

Psychogenic causes are more prominent in the younger population. 

If you get erections during the day, non-organic causes are more likely.


Your doctor will diagnose erectile dysfunction. They can use the International Index of Erectile Function (IIEF-5) to measure the severity objectively. 

Possible scores are: 

  • Severe = 5-7

  • Moderate = 8-11

  • Mild to moderate = 12-16

  • Mild = 17-21

  • No ED = 22-25 

Physical examination

A physical examination includes taking your vitals, including your blood pressure and heart rate. Your doctor may also examine your penis to check for any apparent abnormalities. This includes checking the peripheral blood vessels for issues. 

Psychosocial history

Psychosocial history is an essential part of consultation between you and your doctor. Certain clues in your history can direct the doctor toward non-organic causes, such as life events or a previous history of mental health issues.

Other tests your doctor may request


A penile doppler ultrasound (PDDUS) measures blood flow to the penis before and after a vasodilation agent. An improvement in blood flow indicates a cardiovascular problem, which your doctor can target with treatment.

Nocturnal penile tumescence test

Nocturnal penile tumescence test (NPT) detects nighttime erections through a special electronic device. The absence of erections indicates an organic cause. However, doctors rarely use this test because it is inaccurate and inconvenient. 

Injection test

The (intracavernosal) injection test involves the doctor injecting a medicine into the base of your penis to try and produce an erection. An erection indicates blood flow to the penis is okay, and other factors are more likely to be at play.

Blood test

Blood tests investigate certain risk factors for organic causes. This includes diabetic markers such as cholesterol, triglycerides, and blood glucose levels.


There are a wide variety of treatments for ED. Typically, first-line options include lifestyle modifications to reduce risk factors, oral PDE5 inhibitors (PDE5i), counseling, and vacuum pumps. If these treatments are unsuccessful, your doctor may suggest surgical and vascular implants.


Doctors commonly use oral PDE5 inhibitors to treat ED. These include sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis). They increase blood flow to the penis by preventing the action of PDE5, which makes your penis flaccid.

You have probably heard of Viagra as the wonder drug to treat ED. This may be the first medication your doctor will prescribe. It is a relatively safe drug; however, it is dangerous in combination with nitrates, causing low blood pressure and potentially contributing to heart attacks. 

One literature review⁵ reported one study found the ability to get an erection increased by 68%-71%. 

In the same study, it was reported that, after one year of using Viagra, 96% of participants said that they were satisfied with the medication and its effectiveness was 99%.

Your doctor may prescribe other medications depending on the cause of the ED. For example, your doctor will prescribe supplemental testosterone if you have hypogonadism. Studies report mixed results. One review found that erectile function improvement took over three months to occur. 

Talk therapy

Counseling can help you understand that this is a common condition triggered by many psychological factors. Non-organic cases benefit the most from this treatment. You can also involve your partner if you or the doctor believe it would help. 

Vacuum pumps

A vacuum pump is a device also known as a penis pump. You place the pump over your penis to create negative pressure, forcing blood into the penis to produce an erection. You may need an additional physical constriction at the base of the penis to prevent blood from leaving. This method is not well-tolerated by all people due to side effects such as bruising, numbness, and coldness. 


Surgical options are available for erectile dysfunction. 


Implants can be shaped or inflatable. People generally prefer inflatable penile prostheses due to the extent of flaccidity they can produce. One study⁶ reported a 90% satisfactory response.

Vascular surgery

If the blood vessels to your penis are not working, your doctor may suggest vascular surgery. Here, your surgeon uses the inferior epigastric artery in your lower abdomen and connects it to your penis. Studies⁷ show varied results, with one demonstrating that approximately half of those who had vascular ED surgery were cured after 2-5 years.

Managing ED


Kegel exercises

Kegel exercises can strengthen the pelvic muscles. Some evidence⁸ suggests improvement of erectile function. Kegels are minimally invasive and easy to do at home.

Aerobic exercises

Exercising improves your body’s ability to pump blood around, including to the penis. One study⁹ demonstrated that 40 minutes of aerobic exercises four times a week could improve symptoms. 


Eating a balanced diet is vital for your general health. Research¹⁰ has found associations between a healthy diet and improved ED. 

One study¹¹ published in the Journal of the American Medical Association investigated the impact of weight loss on erectile dysfunction by advising participants to decrease their calorie intake and increase physical activity over two years. At the end of the experiment, they found that a third of their participants’ sexual function returned after following a healthier lifestyle and weight loss.

When to see a doctor

You should seek medical advice if ED is significantly impacting your life. The underlying cause of your ED determines how your doctor will treat it. Do not take any medication without first obtaining medical advice.

The lowdown 

You’re not alone if you’re experiencing ED, as it’s relatively common in all ages. The good news is that your doctor can successfully treat ED through psychological, medical, or surgical intervention. 

Keeping on top of your general health ensures your body can function properly. You can achieve this through exercise and a good diet. 

If you are concerned about ED, consult a medical professional to find a course of treatment that can help.

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