I tried adding just 60mg of npp with 500 test and got firey nipples 3 days in, even with p5p, vitamin e, and zinc. Then I read about how test combined with nandrolone is what causes issues so I stopped the test and waited for it to mostly clear my system. Then I started npp 300mg/week with 25mg dbol a day for enough aromatization. Within 2 weeks I was up to 700 NPP. I would have gone higher if my npp was stronger than 100mg/ml. And it's true. I had no sides effects when I dropped the test. Workouts were excellent. I got stronger every week. But after a month I decided it wasn't for me and switched back to test solo. NPP makes me nice and relaxed and chill all the time. I felt lazy around the house. I prefer the more aggressive, energetic side of me that test gives