Hello I was treated for prostate cancer five years ago ,twenty sessions of radiotherapy and was on hormone pills for three years,in that time to now I've not been able to get a proper erection, feeling started coming back about one and a half years ago but t to this date can't get erect enough for sex ,tried loads of pills off the internet and now trying 100mg Viagra that the doctor has prescribed ,is their anything else I could do like testerone tablets?