PDE5 Inhibitors

PDE5 Inhibitors Overview:

• PDE5 inhibitors are a group of medications often used to treat erectile dysfunction (ED).
• Erectile Dysfunction is often regarded as the most popular kind of sexual dysfunction in males, and it grows more prevalent as men age.
• phosphodiesterase type 5 inhibitors often serve as the first choice of therapy for ED caused by the inadequate blood circulation to the penis.
• PDE5 inhibitors are drugs that increase blood flow to specific tissues, including the penis. They function by blocking the function of phosphodiesterase-5, an enzyme in the smooth muscle cells of blood vessels.
• PDE5 inhibitors that are commonly accessible today include Viagra® (Active Ingredient sildenafil), Cialis® (tadalafil), Levitra® (vardenafil), and Stendra® (avanafil).

What are PDE5 Inhibitors?

• PDE5 inhibitors, also known as phosphodiesterase type 5 inhibitors, are drugs that limit the effects of cGMP-specific phosphodiesterase type 5 — an enzyme that regulates the size of blood vessels that supply the penis and other areas of the body.
• PDE5 inhibitors were first intended to treat cardiovascular diseases such as angina and hypertension (high blood pressure).
• Some PDE5 inhibitors are also prescribed to treat premature ejaculation, which is another prevalent cause of male sexual dysfunction.
• It is an enzyme present in the walls of blood vessels. It has an impact on blood flow and how cells communicate all through the body.
• PDE5 inhibitors decrease the activity of the PDE5 enzyme. This inhibition softens the blood arteries, hence increasing blood flow.
• PDE5 inhibitors may be used to treat ED or pulmonary hypertension.
• They improve erectile function by increasing blood flow to the penis in persons with ED.

PDE5 inhibitors may benefit persons with pulmonary hypertension by:

• regulating blood flow to the lungs' arteries
• boosting the flow of blood to the lungs
• blood pressure reduction

PDE5 inhibitors may potentially help treat heart problems, hypertension, and cancer, according to research.

How do PDE5 inhibitors function?

PDE5 inhibitors function by preventing the activity of the enzyme phosphodiesterase type 5, or PDE5.

The PDE5 enzyme degrades cyclic guanosine monophosphate, or cGMP, which is essential for relaxing soft muscle tissue and regulating blood circulation in several areas of the body, including the penile erectile tissue. Your neurological system sends neurotransmitters, or hormonal activity, to the corpora cavernosa, the soft, sponge-like penile tissue which constitutes the majority of your penis when you are sexually aroused.

These neurotransmitters stimulate the production of nitric oxide, which widens the blood arteries that nourish your penis. The corpora cavernosa begins to swell as blood rushes to your penis, resulting in a bigger, harder erection.

When the actions of PDE5 are blocked, cGMP levels rise and the penile arteries expand, which makes it easier to achieve and maintain an erection.

PDE5 inhibitors also have an effect on the pulmonary vasculature (blood vessels within the lungs) and the lower urinary tract.

What Are PDE5 Inhibitors Used to Treat?

PDE5 inhibitors are used to treat a range of illnesses that affect body regions in which the PDE5 enzyme controls blood flow. 

Erectile dysfunction (ED):

• PDE5 inhibitors are well recognized for their impact on erectile dysfunction.
• PDE5 inhibitors are now regarded as the reference standard in the treatment of erectile dysfunction.
• They are not only incredibly powerful, but they also act swiftly and may last from around a few hours to more than a day.

Pulmonary Hypertension (PH)

• PDE5 inhibitors are given to alleviate pulmonary hypertension, a type of high blood pressure affecting the pulmonary arteries.
• Shortness of breath, chest discomfort, weariness, and a high heart rate are all indications of pulmonary hypertension, which may disrupt blood flow throughout your body.
• PDE5 inhibitors function as pulmonary hypertension remedies by widening the blood arteries that supply blood from your heart to your lungs, enabling more blood flow.

Benign Prostatic Hyperplasia (BPH):

• Benign prostatic hyperplasia, often known as prostate enlargement, is a highly prevalent disorder that mostly affects elderly men.
• BPH signs include a constant, immediate need to pee, leaking after urination, a desire to urinate in the late hours of the night, and discomfort after ejaculation or during urination. BPH may cause urinary tract infections (UTIs) and renal system injury in the long run.
• Cialis (tadalafil) is currently the only PDE5 inhibitor authorized by the FDA for the treatment of the indications and symptoms of benign prostatic hyperplasia.

Types of PDE5 Inhibitors:

ED may be caused by either psychological or physiological reasons. PDE5 inhibitors can only treat ED caused by physiological causes. Treatment options for psychological causes of ED, such as stress or worry, include counseling.

There are four primary forms of PDE5 inhibitors available:

• sildenafil (Viagra)
• tadalafil (Cialis)
• vardenafil (Levitra or Staxyn)
• avanafil (Stendra)

Let's take a look at each of them.

Sildenafil (Viagra):

• Sildenafil, which is offered as a generic medicine and sold under the brand name Viagra, was the first widely investigated PDE5 inhibitor and is likely the most commonly used PDE5 inhibitor on the market in the tablet form named Cenforce 100, Fildena 100, Kamagra oral jelly.
• It was given FDA approval as a treatment for ED in 1998.
• Sildenafil often takes effect within an hour.
• Sildenafil is now licensed by the FDA for the treatment of erectile dysfunction and pulmonary arterial hypertension.

How long does it last?

Sildenafil is a PDE5 inhibitor with a short half-life that relieves ED symptoms for around four hours.

The minimum intake dosage of sildenafil is 50mg. Depending on the severity of your ED and your reaction to sildenafil, this may be lowered to 25mg or raised to 100mg.

Tadalafil (Cialis):

• Tadalafil, marketed as a generic and as Cialis, is a long-acting PDE5 inhibitor licensed by the FDA in 2003.
• It's known as the "weekend pill" since it may offer erectile dysfunction treatment for up to 36 hours per dosage.
• It normally takes 20 minutes to take action and it should be consumed at least a half-hour before intercourse in the form of tablets like Vidalista 20, Vidalista 60, and Vidalista 80.
• Tadalafil is also authorized by the FDA to cure benign prostate hyperplasia (BPH).

How long does it last?

Tadalafil has the maximum period of effect of any PDE5 inhibitor known, lasting 24 to 36 hours. A common daily dosage is between 2.5 and 20 mg.

Vardenafil (Levitra or Staxyn):

• Vardenafil is a PDE5 inhibitor that's been licensed by the Food and Drug Administration in 2003.
• It is marketed as an erectile dysfunction medication under the trademarks Levitra and Staxyn.
• It's also accessible as a generic drug. It has the quickest onset of any PDE5 inhibitor, taking action in about 10 minutes.
• Vardenafil works similarly to sildenafil, although it gives ED treatment for a somewhat longer period of time.

How long does it last?

Vardenafil typically lasts 5 to 7 hours, although it may last up to 12 hours. Vardenafil is typically taken in doses ranging from 5 to 20 mg per day.

Avanafil (Stendra):

• Avanafil is the most recent PDE5 inhibitor to come to market and has been accessible since 2012.
• Avanafil, also known as Stendra, is a second-generation PDE5 inhibitor. It acts in a similar manner as other PDE5 inhibitors, but its mode of action is more selective, making it less likely to induce specific adverse effects.
• Avanafil has the benefit of acting fast, thus it may be taken just before sexual stimulation. While most ED drugs take an hour to kick in, research reveals that avanafil may give treatment for erectile dysfunction in as short as 15 minutes.

How long does it last?

Avanafil has a higher half-life than vardenafil and sildenafil but a lower half-life than tadalafil, with a half-life of about 5 hours. Avanafil is usually used in doses ranging from 50 to 200 mg per day.

Common Side Effects of PDE5 inhibitors include:

• headache
• flushing
• indigestion
• nasal congestion
• cold-like symptoms
• Visual abnormalities
• Back and/or muscle pain
• Visual abnormalities
• Back and/or muscle pain