Erectile dysfunction (ED) affects the lives of many middle-aged men and their partners to one degree or another. The term erectile dysfunction covers a range of disorders, but usually refers to the inability to obtain an adequate erection for satisfactory sexual activity. Erectile dysfunction can be treated in wide variety of ways. Most of the doctors prescribe Viagra, Levitra, and Cialis for the treatment of erectile dysfunction. Although these medications can help many men to treat ED but not all should use them.

Patients who are taking nitrate drugs should not take these pills because for them it can be very dangerous. Originally developed by Pfizer, viagra, also known as sildenafil citrate, has a lot of benefits to its credit, and has over time, been used as an over-the-counter pill, although it strictly stands as a prescription drug, which obviously implies that it must only be procured after a recommended dosage from a registered physician, for there are things that one can’t handle. It excites your sex appeal, prolongs your sexual intercourse. If you are suffering from ED, you’ve a very good reason to choose this drug but not before prior consultations and knowledge about the dosage and the drug itself. The benefits are far reaching; it could start affecting you in just 30 minutes- depending upon the dosage.

Viagra, like most other drugs used to treat erectile dysfunction, works with a pde-5 inhibitor formula that eventually increases blood flow to the penis, enhancing the quality and longevity of the erections, allowing a more satisfactory sexual intercourse. Millions of men around the world who’ve used this wonder pill have testified to the performance it has helped generate, not just in the bedroom, but in boosting masculine confidence as well.

Since Viagra has an effect to dilate genital blood vessels to maintain an erection, research was done if it has an effect on the human heart. And it was found out that it has potential benefits for the treatment of pulmonary hypertension. And this study was headed by the Johns Hopkins researchers. But before that, Viagra was never thought to have an effect on the heart.

Viagra works to dull the increased heart beat, which is a product of chemically-induced stress. It works to decrease the force needed to pump an excessive amount of blood from the heart to the body.

David Kass, M.D., a cardiologist and study senior author of Johns Hopkins study, and his researchers performed experiments on mice and noticed that Viagra is effective in blocking short-term consequences of hormonal stresses in the heart. Long-term damages of chronic hypertension on the heart is also prevented and reversed by Viagra. Negative effects of heart failure and cardiac hypertrophy on the weakened heart muscles in mouse experiments performed by David Kass, M.D. and his researchers are also reversed by Viagra, but this was not tested on human hearts yet so no solid evidence has been gathered to prove this.

To prove this, they conducted the Johns Hopkins study, and it showed that Viagra also has an effect in slowing heart rate after an injection of dobutamine. Thirty five men and women volunteered to go on the Johns Hopkins study for a period of six months. Necessary measurements of heart function like echocardiogram, electrocardiogram, and blood pressure readings were taken before and after the injection of dobutamine (dobutamine is a synthetic derivative of dopamine that increases heart rate and heart contraction). It showed increased heart rate and increased heart contraction by 150%. Then they were separated into two groups; those who took sildenafil (Viagra) and those who took sugar pill placebo. Dobutamine was again given to the individuals to see what sildenafil and sugar placebo has on the heart. It showed that the first group’s heart rate and heart contraction decreased by 50% while those from the second group increased yet again to about 150%.

The success of the Johns Hopkins study started other researchers on how sildenafil works when it comes to the immediate and long-term effects on the heart and other potential benefits they could get from sildenafil.

But these studies are not yet finished. For now, it is good to know that it inhibits the action of phosphodiesterase 5 or PDE5A from breaking down cyclic GMP, a key molecule that aids in the controlling of stress and hypertrophy of the heart.

Viagra has come a long way since its launch. As Viagra has been in the market for so long, side effects of Viagra have become more obvious. The latest of the side effects found by some German scientists is that higher doses of Viagra (sildenafil) may impair the ability to smell, which is possibly related to an increase in nasal congestion.

They found that the 100-mg dose caused a drop in smelling or “olfactory” ability, specifically odor discrimination and odor threshold, compared with placebo. The 50-mg dose, by contrast, had no effect on olfactory function.

The most worrying side effect is its causing blindness. It is in medical terms called non-arteritic anterior ischemic optic neuropathy (NAION) among patients taking drugs for erectile dysfunction. Out of 43 reported cases, 38 had taken Viagra; four had taken Cialis, and one had taken Levitra. The number of men taking impotence drugs is estimated at more than 25 million, with about 23 million taking Viagra. The potential world market is estimated at 189 million patients.

The market for these drugs began to sputter in 2004; six years after FDA approved Viagra. Manufacturers reported $2.4 billion in sales, at least $1 billion below analysts’ earlier forecasts. Pfizer attributed Viagra’s 11% drop in sales last year largely to competition from newcomers Cialis and Levitra. Analysts cite limited health care coverage for erectile dysfunction drugs and patients’ embarrassment about discussing impotence problems with physicians as the primary factors limiting growth.

Experts are now looking at Viagra for the treatment of the heart. Research shows how Viagra acts above the belt have put the pill on pharmacy shelves in a repackaged form, to help the sufferers of a devastating heart and lung condition. Pulmonary arterial hypertension delivers its blow mainly to young women, killing about half of those afflicted within five years of diagnosis. The condition, which affects about 100,000 people worldwide, causes tiny blood vessels in the lungs to thicken and narrow, often for no apparent reason. The lung damage puts huge pressure on the heart via the pulmonary artery, the big vessel that shunts blood from the heart to the lungs. Patients suffer from poor oxygenation of their blood, weakness and shortness of breath. They often die from heart failure Viagra (sildenafil citrate) is known for opening up blood vessels and could provide an effective and a cheaper option for the treatment of the heart. Experts say the drug might help a wide variety of more common heart and lung troubles. Researchers are even investigating whether the pill could protect mountaineers from the potentially lethal effect on the heart of high altitude and low oxygen levels. Viagra inhibits a specific enzyme, and this helps to dilate blood vessels in the penis, causing blood to rush in and enhancing an erection. The same enzyme also happens to be prevalent in the lung. Experts suspect that the drug dilates blood vessels in the lung and inhibits the growth of cells that block the blood vessels, enhancing blood flow and putting less pressure on the heart. Viagra initially was invented for heart problems but did not show good results and instead was used for the treatment of Erectile Dysfunction. Viagra information can be obtained from many sites on the internet.

As the recorded incidence goes, launch of Viagra in 1998 increased awareness of erectile dysfunction.

Prior to the introduction of the first oral medication to treat this common affliction associated with the aging process, most men simply had to suffer in silence with the sort of resignation they applied to balding or sagging skin.

Erectile dysfunction (ED) is now known to be primarily organic in nature, resulting from vascular, hormonal or neurological complications.

In addition, ED can be a marker for other pathological conditions or undiagnosed organic diseases. On top of the physical symptoms, it significantly reduces quality of life along with depression and loss of self confidence.

Treatments of Erectile Dysfunction

These days, the first line of treatment of ED is oral medication. There are three oral medications available on the market, all of which are PDE-5 inhibitors. These are administered by the patient shortly before sexual activity. Patients can also bring some change to their lifestyle (such as losing weight) to improve erectile quality.

Doctors and patients face a unique dilemma these days. All three oral medications (Viagra, Cialis and Levitra) with different molecular structures and pharmacokinetic properties variable have similar success rates. Apart from this, all three medications are rapidly absorbed from the gastrointestinal tract. Viagra and Levitra reach peak plasma concentrations within one hour and Cialis reaches the same by 2 hours.

Treatment Characteristics

Food, in particular fatty foods, appears to inhibit both Viagra and Levitra but not Cialis when compared with the fasted state.

When taken with food, peak plasma concentrations of Viagra are reduced by 30% and the maximum concentration is delayed by one hour. Food also delays the maximum plasma concentration of Levitra by one hour, with a 20% reduction compared with the fasted state. The pharmacokinetics of each of the drugs is not affected by alcohol consumption although there is a causal link between alcohol consumption and erectile dysfunction. In any case, alcohol should be avoided by patients during ED treatment.

Viagra and Levitra both have a terminal half life of approximately 4 hours and for Cialis it is approximately 17.5 hours. None of the drugs have an immediate onset.

Most studies have demonstrated that the drugs have an onset action of between 30 and 60 minutes but the rate of onset varies between individuals. The PDE-5 inhibitors showed marked differences in their duration of effect. Viagra and Levitra showed 4-5 hours duration of effect while Cialis, consistent with its longer half life, showed up to 36 hours of duration of effect and thereby providing patients with a broad window of responsiveness.

Comparative Studies between Cialis, Viagra, Levitra

Although comparative studies have been conducted to examine the relative effectiveness of each of the drugs, most of the studies eliminated patients who did not respond to Viagra. This can seriously undermine the value of the data produced.

One study by the University of North Carolina concentrated solely on patients for whom Viagra was not successful. This demonstrated in a 12 week study that Levitra was successful for 61.8% of patients for whom Viagra was not successful.

A double blind crossover study has also been conducted to test patient preference between Viagra and Cialis, however no such study has been conducted with Levitra. The study covered 219 patients who were randomized to determine the order in which they received Cialis or Viagra. After 12 weeks the patients were crossed over to the other treatment and of those who wished to participate in the study’s extension period, 70% decided to buy Cialis.

A recent open label multi-centre European study confirmed this with 71% wishing to continue with Cialis compared with 29% wishing to continue to buy Viagra. Taken together, these studies seem to demonstrate that the pharmacological differences between the PDE-5 inhibitors can affect patient preference.

The fact that a patient has not responded to one of the PDE-5 inhibitors does not necessarily mean that he will not respond to one of the alternative treatments from the same family of medicines.

Patients should not be deemed true treatment failures until they have failed to respond to the maximum dosage on at least 8 occasions. In a study, 55% of 137 men who had previously not responded to Viagra became successful after re-education and counselling.

Closing Lines

In any case patients are advised to consult their doctors before taking any kind of erectile dysfunction medication or preparing to buy Cialis, Viagra or Levitra.