Erectile Dysfunction Medication Overview

How does ED medicine work?

Medicines used to treat ED fall under the broad category of PDE5 inhibitors (phosphodiesterase 5 inhibitors). This name refers to how the medicine works inside your body. It’s a bit complicated to explain the specifics of how the medicines work physiologically, but while each is a slightly different chemical, they all produce the same end result: most simply, they increase blood flow to the penis, which helps to improve erections.

The medications come in pill form and are taken by mouth. Depending on the medication, it can take anywhere from 30-120 minutes for the medication to begin working within your body. Once activated, the medication will not trigger an erection in the absence of sexual stimulation, but rather when sexual stimulation is present, the medicine helps increase blood flow to the penis and allows for improved erections. The erection will last the same amount of time as a usual erection. An erection lasting longer than four hours is an emergency that could damage the penis (called priapism). If this happens, you should go to the emergency room.

Are all erectile dysfunction medicines the same?

All erectile dysfunction (ED) medicines are not created equal. While medicines used to treat ED are all considered PDE5 inhibitors and produce similar effective results, each one consists of a slightly different chemical composition.

The four main drugs used to treat erectile dysfunction (tadalafil, sildenafil, avanafil, and vardenafil) also differ in how they are dosed, how long they take to start working, and how long they last in your system. The two most commonly prescribed ED medicines are sildenafil and tadalafil.

Sildenafil versus tadalafil

Here’s a quick comparison between these two medicines.

Cost

Cialis (tadalafil): A little more expensive (about the same price at lower doses; 50 cents to $1 more a pill at higher doses)
Viagra (sildenafil): Less expensive (usually less than $1 per pill)

Dosage

Cialis (tadalafil): 2.5 mg, 5 mg, 10 mg, 20mg
Viagra (sildenafil): 20 mg, 25 mg, 40 mg, 50 mg, 60 mg, 80 mg, 100 mg

Duration (how long it lasts)

Cialis (tadalafil): Up to 36 hours
Viagra (sildenafil): 4 hours

Frequency

Cialis (tadalafil): Taken daily or as needed
Viagra (sildenafil): Taken as needed

Side effects

With any medicine there are many potential side effects. Some of the most common side effects of ED medicines like Viagra, include:

Flushing (10% to 19%)
Headache (16% to 46%)
Stomach ache (3% to 17%)
Visual disturbance (2% to 11%)
Nose bleeds (9% to 13%)

Some serious but less common side effects include:

Dizziness
Priapism (an erection over 4 hours — that can cause penile damage)
Syncope or passing out
Heart attack or stroke
Vision loss
Liver damage

What is the best medicine to treat erectile dysfunction?

That is a good question! Truth be told, there is no best medicine. As mentioned above, there are similar results for both medicines when it comes to getting and maintaining an erection. The best medicine for you depends on your situation. We all have unique and different bodies, and so some find success with sildenafil and not tadalafil or vice versa.

There is also the question of value — what is important or concerning is different for each person. If cost is the driving concern, then you will want to stick with sildenafil.

If you want the medicine out of your system faster, then a good choice would be sildenafil as well. But if you have regular, almost daily sex, then you probably want to consider a daily dosing with tadalafil. Tadalafil allows for more spontaneity because it lasts for 24 to 36 hours as opposed to four hours with sildenafil. Some men have a lot of side effects while taking one, but not the other.

Are there medications that last longer than Sildenafil?

Sildenafil, avanafil, and vardenafil are all shorter acting medications used for ED. Chemically, these three drugs are very similar and have similar effectiveness. Avanafil and Vardenafil ODT (orally disintegrating tablets) work faster, but these all last the same amount of time in the system.

An important distinction between these three medicines is cost. Sildenafil (generic Viagra) is typically significantly cheaper than the other two medicines, in some cases as much as $200 to $300 less per month than avanafil and vardenafil. As a result, sildenafil is much more commonly used than the other two.

Tadalafil is the longest-lasting of the ED medications on the market. Sildenafil, avanafil, and vardenafil are shorter-lasting than tadalafil, which can last as long as 36 hours. Generic tadalafil is also very affordable.

Which ED medicine should I take?

Your choice depends on you. What do you value? What are your concerns? Sometimes, you will need to go through a bit of trial and error to see what works and what does not. And you should not consider a medicine a failure until you have tried it on three to four separate occasions.

What to expect from an adequate dose of ED medicine:

Most ED medicines take about 30 to 90 minutes to enter your bloodstream and start working. These drugs won’t give you an erection automatically. Instead, they should make it easier for your body, when stimulated, to get and maintain an erection that is hard enough for satisfying sex. The erection will still last the same amount of time as a usual erection. Once you ejaculate, the erection should not continue and the penis should soften. You shouldn't have an erection in the absence of sexual stimulation/activity. On average, a sufficient dose of ED medicine gives men an erection lasting about 30 minutes. The medicine may shorten the refractory period for some men, allowing them to have a new erection sooner after ejaculation. An erection lasting longer than four hours is an emergency that could damage the penis (called priapism). If this happens, you should go to the emergency room.