If abusing a drug causes extreme physical pain before causing permanent physical harm, that strikes me as being more of a feature than a bug. To the extent tha

If abusing a drug causes extreme physical pain before causing permanent physical harm, that strikes me as being more of a feature than a bug. To the extent that caffeine is safer than cocaine even though they're almost pharmacologically identical then that's the only reason, in terms of caffeine quickly becoming unpleasant after a certain dose.