Sildenafil is a worldwide famous drug that is used for the therapy of erectile disorders and pulmonary hypertension. Initially it was created by American scientists as a treatment for cardiovascular diseases. Although even the first investigations in 1998 demonstrated that new medication could be a perfect treatment for the erectile dysfunction. Sildenafil acts by inhibiting a specific enzyme, that promotes blood flow to the penile tissue. Together with other PDE5 inhibitors (such as Cialis and Levitra), it is recognized as a drug of choice for ED treatment. Nevertheless, nowadays sildenafil is used also for the therapy of pulmonary Hypertension officially, as a medical prescription.
PAH: What does it mean?
Pulmonary arterial hypertension is a specific state characterized by rapid increase of blood flow, following with reconstructing of small vessels. This disorder may lead to a failure in the right ventricle and finally to the death. The nitric oxide pathway plays a significant role in the development of pulmonary arterial hypertension. cGMP-specific PDE5 inhibitors target the enzyme that causes this state by stimulation the dilatation of blood vessels. Thus blood pressure decreases.
PAH is quite a widespread problem among adults. Its untreated survival is 2–3 years from the time of diagnosis. And the worldwide epidemiology is about 4 cases per million. The higher incidence rate is in female group with huge levels of mortality among pregnant women. Survival rates for all patients vary from 49% to 91%. Chronic pulmonary hypertension is treated surgically only in few selected centers (because of the difficulties with procedure). However, common ways of the recently discovered pulmonary arterial hypertension treatment include taking special medications, e.g. PDE-5 inhibitors.
How Viagra from Canada may help in Cardiovascular therapy?
A lot of surveys confirm effectiveness of sildenafil in pulmonary arterial hypertension management. It is proven that the active ingredient of Viagra from Canada improves exercise capacity and indicators of clinical recovery. Sildenafil is recommended as one of the options of choice for PAH management to those patients who have no precautions to calcium-channel blocker therapy or if the prescription is not effective.
In 2013 Chinese researchers published results of a systematic review confirmed efficiency and safety of sildenafil in pulmonary hypertension treatment. Analysis that involved 545 patients showed that in comparison to placebo, examinees taking sildenafil had a better performance in PAH and improved their health indicators in 6 minutes walk distance. However, there was not any notable positive effect on mortality. Nevertheless, sildenafil was recommended for PAH treatment and its efficiency was confirmed again.
The first institute that approved sildenafil for PAH treatment in 2005 was the United States FDA. Marketed as Revatio, sildenafil was used for the therapy of pulmonary arterial hypertension. When, in 2009 other PDE5 inhibitor, tadalafil, came to the PAH pharmacy, these medications became sustainably associated with officially approved and effective ways of pulmonary arterial hypertension treatment. Tadalafil, as well as sildenafil, is taken orally in a recommended dose that is defined individually by therapist for each patient.
Precautions and side-effects
Most common side-effects from taking sildenafil for PAH treatment include headache, dyspepsia, back pain, myalgia and flushing. Contraindications to taking PDE5 inhibitors are common for all patients. The full list of possible precautions to taking sildenafil is still under research. Although such frequent circumstances as taking nitrates, decreased liver or renal function, hypotension, recent heart attacks and some hereditary regenerative disorders are well known. Due to the high mortality in pediatric group, the U.S. Federal Drug Administration does not recommend sildenafil for young patients under 18 years of age.
A lot of clinical surveys showed that most common side-effects from taking sildenafil for ED or PAH treatment include headache (up to 40% and more), indigestion, vision disorders and flushing. Some patients experience sudden hear loss and non-arteritic anterior ischemic optic neuropathy, but these states are quite rare. To eliminate the risk of serious heart disorders or other unwanted consequences from sildenafil taking, it is strongly recommended to consult with your doctor before choosing sildenafil for the treatment of pulmonary arterial hypertension. Self-treatment may result in a serious deterioration of all health indicators, regardless of age, sex and general state of PAH patients.