Erectile Dysfunction

Which Drug For Erectile Dysfunction?

April 6, 2021

Oral medications are usually the first line of treatment for anyone dealing with erectile dysfunction. The most common medications are sildenafil (Viagra®), tadalafil (Cialis®), and vardenafil (Levitra®). They all work in similar ways by inhibiting the natural enzyme PDE5 (phosphodiesterase-5) and enhancing the effects of nitric oxide, a natural chemical the body produces that relaxes the muscles in the penis. This relaxation increases blood flow and allows for erections to be achieved and maintained in response to sexual stimulation. 

Whether or not a drug is the best option for you will depend on your health, medical history, and your physician's discretion, as the most effective ED medications require a prescription (that's where Rex MD can help).

The most common drug use by men in the U.S. – and the most likely to be prescribed – is sildenafil (Viagra®) as it’s been on the market for over 20 years and its side effects are well-understood. But among these top ED medications, there really is no wrong or bad option, as they all work similarly.

But there are differences that may influence your selection.

What is Erectile Dysfunction? 

The definition of erectile dysfunction is having regular difficulty in getting or maintaining an erection sufficient satisfying sexual intercourse. The key word there is “regular” because it's normal for men to occasionally have problems getting erect, especially during periods of extreme stress or anxiety. 

However, when successful erections become more rare than unsuccessful erections, or if they stop happening altogether, it's time to think about what's going on. 

Erectile dysfunction can be a warning sign that something more serious is going on with your health. About 20% of cases end up with someone discovering they have an undiagnosed health condition such as heart disease, high blood pressure, high cholesterol, diabetes, or depression.  Erectile dysfunction can also be the result of being overweight, smoking, drinking too much alcohol, certain types of medications, stress, relationship difficulties or hormonal imbalances. In that sense, erectile dysfunction can be a warning sign for greater issues.

Research suggests erectile dysfunction affects as many as half of all guys over the age of 40.

While erectile dysfunction can be frustrating, it can also be resolved through a variety of approaches, including both lifestyle modifications to address the conditions above, and prescription medications.

Some simple tests under the care of a treating physician can help determine the cause of your erectile dysfunction; even if it isn't easily reversible, medications that treat erectile dysfunction are safe, easily available, and effective in the majority of instances.

How Do Erectile Dysfunction Medications Work? 

Each drug for erectile dysfunction, sildenafil (Viagra®), tadalafil (Cialis®) and vardenafil (Levitra), is classified as a PDE5 inhibitor. For an erection to happen, a compound called nitric oxide sends a message to the tissues of the penis (known as corpus cavernosum), which causes them to relax and to fill with blood. The erection ends when another messenger called phosphodiesterase 5, or PDE5, is released. A PDE5 inhibitor helps erections by slowing the “off switch” in order to maintain the erection long enough to engage in satisfying sexual activities. These medications work to slow the end of an erection but do not help to create them. Stimulation and arousal will still be required. 

What Are The Differences Between Erectile Dysfunction Medications? 

All of the most popular FDA-approved erectile dysfunction medications have demonstrated safety and effectiveness. While they all work by the same mechanism of action, there are some differences between them. For example, sildenafil (Viagra®) works quickly and remains the most popular ED medication globally, while tadalafil (Cialis®) can work through an entire weekend, and can even be taken in a low dose daily. All of these are available inexpensively as generics now, and some people even prefer to alternate between medications, depending on their lifestyle or relationships status. 

Sildenafil (Viagra®)

  • How do you take it? Sildenafil is available in 20, 25, 50 and 100 mg doses and is typically taken as a single pill in the 1-4 hours before sexual intimacy. For best results, wait about one or two hours after eating before taking it. If this can’t be avoided, then stick to a light and low-fat meal. Fatty meals and alcohol can prevent sildenafil from working effectively. Sildenafil should not be taken with a heavy meal.

  • How quickly does it work? The effects can start in as little as 15 minutes, but most men will have to wait about an hour before the maximum effect kicks in. Sildenafil will normally continue working for somewhere between three and five hours.

  • What's the dose? For most guys, the typical sildenafil starting dosage is 50 milligrams. If you're experiencing side effects, you may choose to reduce the dose down to 25 milligrams. If this starting dose isn't working, your doctor may have to increase the dose up to 100 milligrams.

Tadalafil (Cialis®) 

  • How do you take it? Tadalafil comes in a variety of doses for both daily and on-demand use, at 2.5, 5, 10, and 20 mg doses. The two higher doses are taken in the hours before sexual intimacy, though it's known for its ability to work for an entire 36 hours. Tadalafil is unaffected by food, and it can be taken before or after eating with no consequences. It can be taken when needed, or regularly depending on desired results. 

  • How quickly does it work? The effects of tadalafil can be felt as soon as 15 minutes, but generally you will have to wait about two hours for it to reach maximum effectiveness. Tadalafil will stay in your body for a few days, so erections can be achieved at any point in this time period for most men.

  • What’s the dose? The typical starting dose for tadalafil is 10 milligrams for on-demand use. It can be lowered to 5 milligrams or upped to 20 milligrams depending on your response. For daily use, the dosage typically begins at 2.5 or 5 milligrams.

Vardenafil (Levitra®) 

  • How do you take it? Vardenafil comes in 5, 10 and 20 mg doses for use on-demand in the hours before intimacy. Similar to sildenafil, vardenafil should not be taken with food. For best result, men should wait about an hour after eating before taking vardenafil, but a light and low-fat meal probably won't impact its effectiveness significantly.

  • How quickly does it work? This drug may start working as soon as 15 minutes after taking it and will reach its maximum effectiveness around 45 minutes. After this, it will continue working for about four to five hours. 

  • What’s the dose? The typical starting dose for vardenafil is 10 milligrams, but depending on results, can be reduced to 5 milligrams or increased to a maximum of 20 milligrams. A physician can help with this process.

How Effective Are These Medications, and What Are the Side Effects? 

There have been few studies to directly compare sildenafil (Viagra®), tadalafil (Cialis®) and vardenafil (Levitra®), but there have been hundreds of studies that have found each one to be fairly effective at preventing erectile dysfunction. 

All three medications resulted in successful penetrative sex for 65% to 80% of men, compared to 30% of men who received a placebo. 

The most common side effects for these PDE5 inhibitors include:

  • Headache or migraine
  • Flushing 
  • Nasal congestion or runny nose
  • Indigestion or nausea
  • Vision changes, such as blue tinge, light sensitivity or blurred vision
  • Muscles aches
  • Back pain

Some of the side effects are different depending on the drug. 

For example, sildenafil has a higher risk of vision changes than tadalafil. 3% of people who take sildenafil may experience vision issues that last a few hours. Tadalafil has a slightly higher risk of muscle related pain than sildenafil or vardenafil. 

For the most part, users are not particularly bothered by the side effects of these medications, and most of them do not last for long. The only serious side effect of taking PDE5 inhibitors is that they may lower your blood pressure. This will most likely not affect the average user unless they're taking blood pressure medications or dealing with underlying health conditions. A sudden drop in blood pressure can cause dizziness, falling, blacking out, or even a heart attack. If you take any kind of nitrate medication like nitroglycerin then you should not be using any kind of erectile dysfunction medication. 

Consult a physician before trying any erectile dysfunction medication.

How Much Do Erectile Dysfunction Medications Cost? 

The cost for erectile dysfunction drug therapy will vary considerably based on a few factors such as pharmacy price, prescription co-pays, and your health plan coverage. Even if private insurance covers ED medications, you may be limited to a few doses per month. 

Here are a few things you can do to help with costs:

  • Shop around because pharmacy prices can vary dramatically. There are plenty of web-based tools that can help you to compare ED prices easily. Rex MD offers industry-leading prices on all of the most popular medications.
  • Ask your doctor about pill splitting, where you purchase pills in a higher dosage than you might need and then manually divide them into smaller doses.
  • Explore manufacturer discount programs. These will allow you to obtain a limited supply of medications that may not be covered by your insurance.

It's increasingly more compelling to avoid the hassles of insurance and a doctor visit byusing telemedicine providers like Rex MD. Rex MD sells generic ED medications directly at affordable prices, and your membership includes a free physician consultation for evaluation and a prescription, if appropriate.

The Takeaway: The most effective and common drugs for erectile dysfunction are sildenafil (Viagra®), tadalafil (Cialis®) and vardenafil (Levitra®). They are all effective and only have a few differences between them. 

Sildenafil is the most common erectile dysfunction on the market and often the cheapest drug; it also has the longest safety record as well, having been approved for use in the U.S. in 1992. Sildenafil's primary shortcoming is that it must be used within a few hours of expected intimacy, and it should be not be taken after a fatty meal. Tadalafil's effects can last much longer, making it more useful if you have a fairly active and regular sex life or don't want to plan ahead: its effects can last 36 hours, hence it's nickname as "the weekend pill." In addition, tadalafil is not affected by food, which can make it easier to use. Vardenafil has no significant advantages, but some men find that it's the most effective option for them. For some men, trial and error with each of these medications may help them find the most effective or advantageous for them.

At the end of the day, it will ultimately be you and your doctor’s decision on which ED medication is the best for you. Cost and lifestyle are likely to be the deciding factors, and Rex MD's licensed physicians can help.

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Which drug for erectile dysfunction? - Harvard Health

What is the most effective pill for ED? - Medical News Today

"Erectile dysfunction: Viagra and other oral medications" - Mayo Clinic