I am experiencing some erectile dysfunction. My erections are not as hard as they used to be and I do not stay hard for long. I attribute my erection problems to the Propecia tablet that I take daily. As you know, Propecia is 1 mg. of finasteride. Propecia has been shown to cause side effects such as erectile problems in a small minority of users. Unfortunately, I appear to be in that small minority. Once my erection problems surfaced, I began looking for a solution. I do not want to stop taking Propecia because it has done wonders for my hair. Propecia has halted my hair loss and has re-grown considerable amount of hair. Thus, I need to address my erection problems while still being able to take Propecia. I read that L-Arginine could help with my erectile problems and that it works similar to Viagra. Thus, I began taking L-Arginine, 1500 mg. twice a day. It has helped but it has not solved the problem. I went to my doctor and he gave me a prescription for Viagra, 50 mg. My question is this: Is it safe to occasionally take Viagra if I also take L-Arginine? Are there are any potential contra indications in that Viagra should not be taken by a person who takes L-Arginine? If so, is the contraindication just for that day? In other words, would I be safe if I did not take L-Arginine on the day I took Viagra? Or, do I have to stop taking L-Arginine completely if I am going to occasionally take Viagra (i.e. take Viagra once a week)? Thank you for your response.