alprostadil can cause the following side effects: changes in your blood pressure, dizziness, headache, pain in your penis, urethral burning or bleeding, reactions at the site of the injection, such as swelling. you should always read the patient information leaflet.

hormone therapy

if your doctor thinks that your erectile dysfunction is related to your hormones, chances are you will be referred to a hormone specialist (an endocrinologist) who will look to rebalance your hormone levels (probably with a series of hormone injections.)

surgery

surgery is a last resort for treating impotence. it is normally only recommended for younger men who have seriously injured their pelvic area or men who have an anatomical problem with their penis. 

it used to be the case that if a man had a blockage in the blood vessels leading to the penis, then surgery could be used as a way to unblock these to allow the blood to flow again. however, evidence shows that this surgery is often not successful in the longer term, so it is now rarely used to treat this problem.  

penile implants are another type of surgery. this is not normally available on the nhs, but about 75% of men who have it are satisfied with it.