Viagra – The effective treatment for Erectile Dysfunction

The advent of Viagra took the world by storm when it was first introduced to the US market in 1998, revolutionizing the treatment of erectile dysfunction (ED) (also known as impotence). Although originally studied as a drug for the treatment of hypertension (high blood pressure) and angina, it became clear that Viagra could induce marked penile erections. It was the first oral ED treatment to be approved by the US Food and Drug Administration (FDA) and quickly gained a reputation as an effective ED treatment. Today, Viagra still remains the leading oral treatment for ED.

ED refers to the condition where a man has problems in achieving and/or maintaining an erection. ED varies greatly between individuals - a man may be able to get an erection but it is not hard enough to achieve penetrative sex, or he may be able to achieve a hard enough erection but it does not last long enough for sexual activity to be successfully completed or he may simply not be able to get an erection at all.

Most men experience some form of erectile difficulties at some point in their lives, but these problems are usually only temporary in nature and clear up by themselves. However, if erection difficulties persist, medical advice should be sought. ED is a genuine medical condition, and whilst it cannot be cured, once correctly diagnosed, effective help to ameliorate the symptoms is available.

ED is an extremely common medical condition. It is estimated that ED affects over 30 million men in the US alone.

There are a number of different reasons why ED develops, although, as with so many other conditions, the incidence of ED increases with age. In the majority of cases (about 70% of all cases), ED has a physical cause. The most common causes include:

• High blood pressure; 65% of men with high blood pressure also have ED
• High cholesterol; Having high cholesterol increases the risk of developing ED by 80%
• Heart disease
• Diabetes; Up to 85% of diabetic men have some form of erection problem
• Prostate problems

Other causes include spinal injuries, depression, stress and the effects of certain medications (including some treatments for depression, cancer and heart disease). But, whatever the reason for ED, Viagra is usually effective in treating it because Viagra works on the actual physical mechanics of the penis becoming erect.

The active ingredient in Viagra is sildenafil citrate which belongs to a group of drugs known as ‘PDE5 inhibitors’. Viagra works by inhibiting the actions of PDE5 (phosphodiesterase type-5), an enzyme that occurs naturally in erectile tissue. PDE5 interferes with erectile function because it breaks down the chemical cyclic Guanosine Monophosphate (cGMP) which plays a crucial role in making the penis properly erect.

The penis becomes erect as a result of a chain of reactions. When a man is sexually stimulated nitric oxide is released from nerve terminals and endothelial cells. This causes the smooth muscle cells in the blood vessel walls of the corpus cavernosum ( the two spongy tissue erectile bodies found in the shaft of the penis) to produce cGMP. The effect of cGMP is to relax the smooth muscles and by relaxing, they open wider to allow more blood to flow in which fills up the corpus cavernosum. At the same time, blood pressure in the penis is increased because the veins that carry blood away from the penis close down. Blood is, therefore, effectively trapped inside the penis and the penis becomes hard and erect.

Viagra works by being a potent and selective inhibitor of PDE5. If PDE5 binds with cGMP, cGMP can no longer work properly and ED occurs. The molecular structure of Viagra’s active ingredient sildenafil is very similar to that of cGMP. Viagra competes with PDE5 to bind with cGMP, which results in more cGMP and better erections.

As a PDE5 inhibitor, Viagra can be used effectively and safely by men of all ages whether they have erectile problems all of the time or just some of the time. This is true even if the ED sufferer has other health problems such as diabetes, high blood pressure, high cholesterol, heart disease, prostate problems or depression. This is particularly important given that, in many cases, it is these other health issues that are the underlying cause of the ED. Viagra can also be safely taken with many of the medicines taken to treat these conditions although, before taking Viagra with other medicines, appropriate medical advice should be sought.

Some men fear that taking Viagra might result in them having embarrassing instant erections. This worry is entirely groundless. Viagra will only work if a man is sexually stimulated and the nitric oxide/cGMP system has been activated. If Viagra is taken and no sexual stimulation follows, no penile erection will be experienced. This is because Viagra only works on inhibiting PDE5 which is only activated once a man has become sexually stimulated and nitric oxide has been released and cGMP produced. This also means that once sexual activity has been completed and the man is no longer sexually stimulated, any erection will go away.

Viagra is not an aphrodisiac - it does not increase libido. It only works upon the actual physical mechanics of obtaining and maintaining an erection. It is designed purely for those men who have ED. It does not offer any form of birth control nor does it provide protection against sexually transmitted diseases.

It is recommended that Viagra should be taken about 30 minutes to 1 hour before having sex. This is because, once taken, Viagra works very quickly - usually within 30 minutes (although some studies report that it can work in some men in as little as 14 minutes). However, it is not a problem if a man is not sexually stimulated within 30 minutes to an hour after taking Viagra, because Viagra works for 4 hours. This gives a man plenty of time to become sexually stimulated whilst the Viagra is still active in his body. For fastest results, Viagra should be taken on an empty or after eating a low fat meal (high fat foods can slow the body’s ability to absorb Viagra). Generally Viagra works the first or second time - but for some men it can take a little longer. 
Dosage

Viagra comes in 25mg, 50 mg and 100mg tablets.

It is usual to start Viagra with a 50mg dose although many men find that 100mg works better. Viagra can be taken once a day, every day. If Viagra does not work after a few times, a simple dose adjustment maybe required.

For men aged over 65 or those suffering from serious liver problems, your doctor may prescribe the lowest dose (25mg) initially.

If you are taking protease inhibitors, your doctor may also recommend a 25mg dose and this may be limited to a maximum single dose of 25 mg in a 48-hour period.

Your doctor may also start you on a lower dose if you have prostate problems or high blood pressure and are taking alpha blockers.

Side effects

Viagra has a well established safety profile and is generally well tolerated. The most common side effects of Viagra are headache, facial flushing, and an upset stomach. Less commonly, bluish vision, blurred vision, or sensitivity to light may briefly occur.

In rare instances, men taking PDE5 inhibitors have reported a sudden decrease or loss of vision or hearing. Although these events have not been directly linked to taking PDE5 inhibitors, if you do experience a sudden decrease or loss of vision or hearing, stop taking Viagra and seek immediate medical assistance.

If you experience an erection lasting more than 4 hours, seek immediate medical help to avoid long-term injury.

Warnings

Viagra must not be taken if you take nitrates (often prescribed for chest pain) as this may cause a sudden, unsafe drop in blood pressure.