Cialis samples in canada Cialis samples in canada kamagra online now kamagra online pharmacy Sildenafil has been found to be effective and safe in the treatment of erectile dysfunction in men with stable heart disease due to atherosclerosis of the coronary arteries, provided that they are not on any type of nitrates. The real concern is not as much the safety of sildenafil but the risk of sexual activity in triggering heart attacks or abnormal heart rhythms in patients with heart disease. What Causes Erectile Dysfunction? Common causes of ED include diseases that affect blood flow, such as atherosclerosis (hardening of the arteries) or venous leakage (weak veins); nerve diseases; psychological factors, such as stress, depression, and performance anxiety; and injury to the penis. Chronic illness, certain medications, and a condition called Peyronie's disease (scar tissue in the penis) can also cause ED. Sexual Problems in Men: A sexual problem, or sexual dysfunction, refers to a problem during any phase of the sexual response cycle that prevents the man or couple from experiencing satisfaction from the activity. The sexual response cycle has four phases: excitement, plateau, orgasm, and resolution. order generic viagra online canada buy viagra online Cialis samples in canada viagra online safely viagra online without prescription Hypertension (high blood pressure): People with essential hypertension or arteriosclerosis have an increased risk of developing erectile dysfunction. Essential hypertension is the most common form of hypertension; it is called essential hypertension because it is not caused by another disease (for example, by kidney disease). It is not clearly known how essential hypertension causes erectile dysfunction; however, those with essential hypertension have been found to have low production of nitric oxide by the arteries of the body, including the arteries in the penis. High blood pressure also accelerates the progression of atherosclerosis, which in turn can contribute to erectile dysfunction. Scientists now suspect that the decreased levels of nitric oxide in patients with essential hypertension may contribute to erectile dysfunction. Erectile dysfunction, heart disease and other vascular diseases: Although ED can be caused by various conditions, about 7 in 10 cases are due to narrowing of the small arteries in the penis. This causes reduced blood flow to the penis. This is the same problem that can occur in other blood vessels. For example, narrowing of the blood vessels in the heart (the coronary arteries) is a cause of angina and other heart problems. Narrowing of blood vessels to the brain is a risk factor for having a stroke. Narrowing of blood vessels in the legs can cause peripheral vascular disease. Depression and anxiety: Psychological factors may be responsible for erectile dysfunction. These factors include stress, anxiety, guilt, depression, widower syndrome, low self-esteem, posttraumatic stress disorder, and fear of sexual failure (performance anxiety). It is also worth noting that many medications used for treatment of depression and other psychiatric disorders may cause erectile dysfunction or ejaculatory problems. Therefore, the dose and frequency of tadalafil has to be lowered in the following examples:Men with severe liver disease should not take tadalafil. Men with mild to moderate liver disease should not exceed tadalafil dose of 10 mg once daily.