I would return this question with another one: “Which drugs and with what frequency?” We’re entering a world that is very drugs-positive thanks to the radical 1960s. Whether it’s so-called safe drugs like Prozac or whether it’s more dangerous ones like heroin, the devil is the details.
Character: I can’t go into every drug, but I can explore a common dichotomy that will shed light on this: cocaine versus marijuana. Cocaine has a very high abuse potential and is very damaging to one’s health. So immediately there’s a responsibility issue. Someone doing coke all the time is simply not taking care of their body. Marijuana, on the other hand, has many health benefits, and if your partner is otherwise a responsible person, and has researched the health consequences of it, then maybe you should trust them.
Cocaine has that Dr. Jekyll-Mr. Hyde aspect that’s similar to alcohol, and so there’s trust implications. How can your partner make promises they know they won’t keep when they’re high on coke? How can they be faithful when they don’t know what the coked-out version of themselves will do when they’re traveling on a business trip? Marijuana, on the other hand, is not as personality-altering. The keyword is as. If they’re a completely different person when they’re high, then there will always be trust issues.
There are care and compassion issues in the cocaine vs. marijuana debate too. Cocaine makes people more aggressive, and that may turn you on initially, but does it lead to your partner treating you poorly at other times? Does it make them angry and violent? Marijuana tends to make people more sympathetic, relaxed and empathetic, so it may improve your partner’s compassion for you. On the other hand, it also commonly inspires apathy. So if you’ve had a bad day at work, do you want to come home all the time to someone who doesn’t want to listen to you vent?
It may sound like I’m taking the side of marijuana, and maybe that’s because I’m a Millennial and was born and raised in California, but I really think the implications of your specific partner matter the most, not what any study says. The question should be, “How does this particular drug impact my particular partner?”
Chemistry: If you have bad associations with drugs or just outright are disgusted by the lifestyle, then this is easy. You’re probably already turned off and are not going on further than the first couple dates. On the opposite end of the spectrum, you may initially have bonded with your partner because of drugs. If so, just be weary of the negative character implications that may crop up from the addiction. Even if you’re not into judging the character of your partner, character issues will eventually become chemistry issues, and you’ll associate the drugs with their transgressive behavior.