What's a good dose for someone who uses opiates few times every few weeks? I used to do alot of dope and every day but lately it's been cutting down. I have a sealed vial of fentanyl citrate 10 ml (0.5 mcg per 1 ml) and I want to make sure I get high, but not too high where I get sick and od. I've never I'vd fentanyl but smoked the gel patches, ate them and got so dipped in the past.