Often, these are prescribed for chest pain called angina. Oral medicines for ED usually work well and cause few side effects. Contact your medical provider if you experience any side effects during treatment. They include dutasteride Avodart, Jalyn and finasteride Propecia, Proscar. The four main medicines taken by mouth for erectile dysfunction are: Avanafil Stendra. This will increase the supply of blood to the lungs and reduce the workload of the heart.Vision changes. Muscle pain. But there are some differences. With Viagra, there is a higher risk of vision changes than with Cialis. Among people who take Viagra or sildenafil, 3% get blue vision that lasts a few hours. On the other hand, Cialis has a slightly higher risk of muscle pain than Viagra and vardenafil. Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include headache and indigestion. Tadalafil . Brand-name Cialis: $ per month (5mg) Generic Cialis (tadalafil): starting at $40 per month (5mg, 10mg, 20mg) Daily generic Cialis (tadalafil): starting at .