At least one in ten men have, at some point, problems getting or holding an erection. Erectile dysfunction (ED) leads to the constant inability to achieve and maintain an erection firm enough to have sexual intercourse. 

Regardless of the cause, ED is the result of vascular alterations that cause blood to reach the penis with problems, preventing erection. Those with ED not only experience sexual and relationship problems but also self-esteem and emotional ones, making it a major health concern even if it is not life-threatening.

Both Viagra and Sildenafil are treatments of choice for improving ED. However, while both drugs have different names, they are the same thing. We explain more below.

Chemicals behind the erection 

Erection is a neuromuscular process that requires three main components: sensory stimulation (the popular pregame), muscle relaxation, and blood supply.

The penis is a smooth muscle structure, i.e. involuntary, that responds naturally to sensory stimuli with erection. For an erection to occur, there must be an exciting sensory stimulus that triggers complete relaxation of the corpus cavernosum, the most important component for the erection, to allow blood to fill it and shape the erect penis.

When any of the above three components have a problem, you do not achieve an erection. Additionally, some natural enzymes called phosphodiesterases 5b> (PDEs) control the whole muscular process by preventing corpus cavernosum relaxation.

The smooth muscle within the corpus cavernosum contains cells that work with chemicals, such as GMP, that fall victim to phosphodiesterase-5 and allow the penis to remain erect. Dysregulation of phosphodiesterase-5 also leads to erectile dysfunction because too much of it causes the corpus cavernosum to never relax, and thus never become erect.

In short, erection is the product of the balance between the stimuli that give rise to it and the regulatory mechanisms that bring the penis back to its normal size and shape. Most cases of ED are related to vascular, neurological, psychological, or hormonal disorders, although some may be drug-related

Treatment for ED: Phosphodiesterase 5 inhibitors 

Phosphodiesterase 5 inhibitors (PD5 inhibitors) are a group of drugs to treat ED. As the name implies, their function is to inhibit the phosphodiesterase 5 to promote relaxation of the corpus cavernosum, and ultimately, the erection.

There are several types, although just a few differences between them, and 4 are commercially approved:

  1. Sildenafil

  2. Tadalafil

  3. Vardenafil

  4. Avanafil

All have the same mechanism of action and similar efficacy. The choice between one or the other depends on your doctor’s criteria and how often you have sex.

As mentioned above, phosphodiesterases are the enzymes that degrade muscle chemicals, such as GMP, and all PDE5 inhibitors focus on preventing them from doing so

It is common for you to read about sildenafil and Viagra, and be confused about whether they are two different drugs, or whether one is better than the other. The truth is that they are the same only Viagra is the trade name, while sildenafil is the main component. In other words, Viagra contains sildenafil.

Both are identical in the following points:

  1. Their active ingredients 

  2. Dosages  

  3. Efficacy 

  4. How long they take to start working 

  5. Duration of drug action  

  6. Safety and side effects  

  7. Restrictions based on your current medical condition or other medications you are taking  

Sildenafil, also known as sildenafil citrate, was initially developed to control heart disease by the pharmaceutical company Pfizer. In the early phases of clinical trials, researchers found it had little effect on improving cardiovascular disease. Simultaneously some volunteers had headaches, visual problems, muscle aches, and coincidentally improved erectile response

Following that discovery, Pfizer began the first clinical trial of sildenafil in men with ED in May 1994 and patented the drug in 1996. It was approved by the FDA in March 1998 and put for sale that same year.

Viagra's patent expired in 2012 for countries outside the United States, allowing the sale of generic sildenafil. Since then, it has become a generic drug and can be manufactured and sold by several companies.

How are sildenafil and Viagra the same?

When talking about sildenafil in terms of effectiveness, dosage, and mechanism of action, we would also be talking about Viagra, and here are some key points:

  1. Sildenafil was the first PDE5 inhibitor sold worldwide. It comes in 25, 50, and 100 mg tablets, and the dosage is modified according to each patient's need. 

  2. As for its way of working and effects, sildenafil starts working from 30 to 40 minutes after taking it, so you should take it almost an hour before sexual intercourse.

  3. Its effects can last up to 12 hours but may diminish if you eat fatty or heavy meals. Similarly, drinking alcohol also decreases its effects and delays erection.

  4. Among all PD5 inhibitors, sildenafil is the most commonly prescribed to treat ED. Many manufacturers compete due to its demand, making it an affordable and accessible treatment for all patients.

Differences between generic sildenafil and Viagra

The main differences rely on price, presentation, and some ingredients. 

Presentation and price

Sildenafil citrate in its generic form is cheaper due to the great competition among manufacturers, which makes it more affordable. Therefore, its packaging is less engaging compared to that of Pfizer's Viagra. 

Inactive ingredients

Some generic sildenafil may have inactive ingredients other than Pfizer Viagra. Some pharmaceutical companies have different suppliers, and the drug formulation may differ among some, but this is of minor significance when comparing effectiveness and safety.

When choosing between Viagra and the generic form of sildenafil, you should consider your budget and whether brand name and prestige mean anything to you.

Viagra is simply the brand name for sildenafil made by Pfizer. Just as Viagra is effective, so is generic, it just does not have the prestige behind the brand name, and often the presentation is not the most on-trend.

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