How do i do substances/substance abuse in D&D?

So I want to do a side quest in a campain I'm planning that focuses on substance abuse, so how do I do that whilst keeping the side quest in?

Do it like the show Arcane, it delves into something like it.

Quote from boss0tron3000 >>

Do it like the show Arcane, it delves into something like it.

Haven't watched that. So can you explain?

Quote from AverageSunGod >>

Quote from boss0tron3000 >>

Do it like the show Arcane, it delves into something like it.

Haven't watched that. So can you explain?

 Not really, it's been awhile. But here's a link to a video to the explanation.

Shimmer (Arcane) Explored - What Is This Mysterious Drug? How Does It Genetically Change People? / Marvelous Videos

https://www.youtube.com/watch?v=NVmDt7aV1PY

*takes notes* Hmmmh that is good.

(It's effect is temp hp but I'll add in an overdose mechanic (could benefit them at a cost?))

Perma-buff to one thing, but a perma-debuff to something else?

Quote from boss0tron3000 >>

Perma-buff to one thing, but a perma-debuff to something else?

Effects end at a long rest or 1 week without use (you entire hp pool is now temp hp and recovers 1d4 per turn) is an idea of mine

Maybe you can make different strands of it, like 'power shimmer' that gives you a buff in strength, but if you overdose, you get a perma-buff to strength but a perma-debuff to intelligence.

Quote from boss0tron3000 >>

Maybe you can make different strands of it, like 'power shimmer' that gives you a buff in strength, but if you overdose, you get a perma-buff to strength but a perma-debuff to intelligence.

I think that's too complicated for a side quest.

OK 👍

Quote from boss0tron3000 >>

OK 👍

And I want the effects to be temporary. No permanent effects (until the lethal od)

You know the players are gonna try to bring it on the full adventure after, right?

Quote from boss0tron3000 >>

You know the players are gonna try to bring it on the full adventure after, right?

That is intended (they keep a small amount at a time)

The first thing you should probably do is check in with your players; it's a touchy subject, and people may not want it popping up in their fun time.

(It's also easy to do poorly. Even players who are fine with it in theory may not be a fan of an approach that strays too far in extreme presentation. (whether it be ham-handed moralizing worthy of D.A.R.E. or "drugs are actually pretty awesome".))

Quote from jl8e >>

The first thing you should probably do is check in with your players; it's a touchy subject, and people may not want it popping up in their fun time.

(It's also easy to do poorly. Even players who are fine with it in theory may not be a fan of an approach that strays too far in extreme presentation. (whether it be ham-handed moralizing worthy of D.A.R.E. or "drugs are actually pretty awesome".))

So what you're saying is. 1: Session 0 needs that included, and 2: it needs finite care and planning.

The campaign my party has been running for the last couple of years has involved a bit of a substance abuse sub-plot. For the record, everyone in my group are all adults (mid-30s to mid-50s), and I cleared all of this in Session Zero. The evil cult the party is fighting has been using a specific drug to enhance their connection to the evil demon god they're trying to summon into the world. Plus there are other characters and NPCs with some positive and some very very negative "recreational substance" involvement. So, like any good over-zealous worldbuilder whose brain won't turn off at night, I created my own little system for how drugs work in game terms. 

So the drugs I made up for game use are: Pixie Dust, Mello Yello, Jack, and Dragonweed (Black, Blue, Gold, Red, Faerie, and Shadow). Each substance has its own stat block which includes things like saving throw DC, onset time, duration of effects, after-effects, chance of developing dependency (addiction), and what the effects of that dependency are. So let's look at one example of a drug stat block. Let's use Blue Dragonweed. 

• Blue Dragonweed
• Onset time: 3d4 rounds.     Duration: (1d4+1) x 10 minutes.
• Con save DC 15.
• Success:  Pleasant tingling in your fingers and toes, and advantage on initiative rolls.
• Success by 5 or more:  Success effects plus resistance to lightning damage.
• Failure:  Occasional painful nerve twitches (no game effect).
• Failure by 5 or more:  Frequent nerve twitches and moderate nerve pain. Disadvantage on Dexterity checks and saves, and disadvantage on concentration checks.
• After-effects:  Moderate numbness and body itchiness for about 10 minutes, disadvantage on concentration checks during that time.
• Dependency Risk:  5% per use (cumulative).
• Dependency effects:  Frequent nerve pain and headaches, disadvantage on dexterity, wisdom, and charisma skill checks and saving throws, and disadvantage on concentration checks.

And of course there are rules for how to overcome dependency (magical, medicinal, and cold turkey options) for each substance. It's probably a bit much, I know. I figure it's easiest to think of a drug as being like a monster, so building a stat block for each one just kinda made sense.