Erectile dysfunction (ED) is the inability for a guy to achieve and maintain an erection firm enough for sex. ED is the same as impotence, but impotence is used less often when referring to this common condition.

ED affects hundreds of millions of men. Statistics from the Massachusetts Male Ageing Study show that about 52% of men experience erectile dysfunction at some point in life.

As a man, it’s normal to have trouble getting or keeping an erection occasionally. However, if you frequently have difficulty getting an erection or maintaining a firm erection during sex, you might have ED.

Erectile dysfunction can occur for a variety of reasons. Sometimes, a psychological issue or nervousness can trigger ED. In other cases, ED can be a sign that you might also have an underlying health problem.

Factors like your use of tobacco products, other medications or alcohol can also contribute to erection issues, making it harder for you to maintain a fulfilling sex life.

When ED occurs at a bad moment, it can affect your self-confidence. Luckily, ED is one of the easiest sexual dysfunctions to treat. Today, a variety of safe, MHRA approved medications and non-prescription treatments are available to help men of all ages treat ED.

The most common symptom of erectile dysfunction is difficulty developing and maintaining an erection during sex. Persistent erectile dysfunction can also affect your sexual confidence and potentially cause you to become less interested in sexual activity.

Difficulty getting an erection
Erectile dysfunction can make it difficult for you to get an erection, even if you’re in the mood for sex. Erection problems can range in severity -- sometimes, you might find it difficult to get any erection, while in other cases you might find it difficult to get a firm enough erection for sex.

Difficulty maintaining an erection
Erectile dysfunction can make it difficult for you to maintain an erection during sexual intercourse. Even if you get an erection before sexual activity without difficulty, you may find it difficult or impossible to keep a firm erection during sex, which can impact your experience, orgasm and ejaculation.

Loss of interest in sexual activity
If you have erectile dysfunction, it can affect your self-confidence and make you avoid sexual activity. Many men with erectile dysfunction feel less interested in sex and lose some or all of their motivation to pursue sexual relationships.

Erectile dysfunction can develop for a variety of reasons. Sometimes, erectile dysfunction is a sign that you might have an underlying cardiovascular health issue. In other cases, ED can be caused by psychological factors such as anxiety or nervousness about sex.

Physical Causes of Erectile Dysfunction
Heart disease, high blood pressure, high cholesterol, Type 1 or Type 2 Diabetes, metabolic syndrome, Parkinson’s disease, sleep disorders, multiple sclerosis, alcoholism and prostate cancer/enlarged prostate

Psychological Causes of Erectile Dysfunction
Stress, anxiety or depression, relationship issues and pornography.

Sources: Translational Andrology and Urology

While you’re probably familiar with some of the most common ED drugs like Viagra and Cialis, there are more choices out there. Not only should you consider prescription drugs, but there are also over-the-counter options as well as non-oral medications. Here is an overview of the different types of ED drugs available:

• Sildenafil (Viagra)
• Tadalafil (Cialis)
• Vardenafil (Levitra)
• Avanafil (Stendra)
• Alprostadil suppository
• Alprostadil injection
• Papaverine
• Phentolamine

Because most ED drugs work similarly, they also have similar side effects. The side effects of ED drugs typically occur while the drugs are active in the body, although they can often last for slightly longer than the drug itself.

This means that if you’re prone to side effects from ED drugs, you may notice them lasting for longer if you use a medication such as tadalafil, which has a very long half-life.

There are seven side effects that are most commonly reported by ED drug users. They are:

• Headaches^*, which are associated with all ED drugs. Headaches are most commonly caused by increased nitric oxide levels, which can increase blood flow and result in a temporary headache.
• Dizziness^*, which is also a result of increased nitric oxide levels. The dizziness from ED medication is typically not severe, but it can potentially lead to discomfort and fainting in people with underlying health conditions.
• Muscle aches, which may also be caused by the increase in blood flow caused by all widely available ED medications.
• Nasal congestion, or a stuffy nose. This typically occurs when ED medications are at peak concentration and reverses as the drugs are metabolised and excreted.
• Facial flush, which can range from mild facial redness to bright red skin that looks like it’s affected by a rash. Like other side effects, this usually reverses as the levels of the medication in your system decline.
• Vision issues, including temporary blurry vision and blue-tinted vision. This condition is called cyanopsia and is thought to result from diminished enzyme activity.
• Digestive issues, ranging from diarrhoea to indigestion and bloating. These are usually temporary and can be made worse by consuming alcohol, caffeine, carbonated drinks and dairy products.

In general, you’ll need to provide some time for your ED medication to start working before you engage in sexual activity. The best approach is to prepare ahead of time and make sure you’ve consumed your ED medication 30-60 minutes before sex, depending on the specific drug and your doctor's recommendation.

Peak effects occur after 120 minutes for Cialis, and 70 minutes for Viagra. Cialis activity is not affected by food. Viagra's effect may be diminished if taken soon after a high fat meal (which may also delay how fast it works). For this reason, Viagra is best taken on an empty stomach.

Effectiveness of all PDE5 inhibitors is similar; although reported effectiveness of Viagra, at 84% is slightly higher than that of Cialis at 81%.7 However, some men prefer Cialis because of its longer duration of effect.