Possible problems with prostheses include mechanical breakdown and infection. Mechanical problems have diminished in recent years because of technological advances. Drug therapy for erectile dysfunction: In a small number of cases, people who have taken sildenafil have complained of headaches, flushing and stomach-ache. It can also cause some visual problems, including an increased sensitivity to light, blurred vision or an inability to tell the difference between blue and green. Men who are already taking medicines that contain nitrates, such as nitro-glycerine (usually for angina or heart disease), are strongly advised not to use Viagra as this is dangerous and may result in a heart attack. Other similar drugs are tadalafil (Cialis)and vardenafil (Levitra). buy cialis online canada buy canadian cialis How does an erection normally occur? When you are sexually aroused, messages from your brain travel down nerves to your penis. Chemicals called neurotransmitters are then released from the ends of the nerves in the penis. Stimulation of the penis can also cause local nerve endings to release neurotransmitter chemicals. best price viagra viagra online online viagra drugstore cheap viagra 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.
