did this once with my barbarian. Basically he'd been the guinea pig for our "Doctor's" chemical experiments and had been extremely addicted. He'd go so far as to not even drink the potions in battle, but smash the bottles into his face to get them in his system faster, kind of a patchwork after a while.
Suddenly the Doctor decided that after watching a barbarian with 2 flails and enough medieval pcp to kill 2 horses rip his way through 10 kobolds and a dragon, that perhaps he had been going too far with human subjects and swore off brewing such addictive substances ever again.
Long story short, Bar-Bar panicked, remembered that dragons are magic, therefore the blood is magic and tried biting into the dragon's throat to get that crimson ambrosia. Rolled a nat 1, bit into the sac that held it's fiery breath weapon and got immolated. he survived... but without his drugs, he slowly drifted into a cold turkey madness that threatened the whole party multiple times. 'twas fun