There are many things that you can try and talking about what will be best for your sex life is important.
You may have to pay for your treatment if you do not have a particular illness that would allow you to have an NHS prescription (specified in a government guideline called schedule 2). The list of illnesses is on the next page. If you need to pay it is only for the drugs and not the writing of the prescription. Chemists can vary in the amount that they charge for the drug so you may want to shop around!
Treatments are used whenever you need to get an erection.