Grades of Drugs are p. 190 Chrome Flesh. Pharmaceutical to reduce Addiction threshold and Designer grade to reduce Crash duration (for something like Novacoke).
Narco Geneware p. 159 Chrome Flesh. It adds dice to Addiction tests (once you're addicted) , Increases Drug effects, and decreases Crash Effects. If you're making a Juicer start here.
Also of interest is Double Elastin p. 160 to reduce Stun damage if your preferred cocktail does stun damage as a crash.
The Drug Tolerant Positive Quality may or may not be needed for a couple more dice of Addiction tests.
Drug interactions / overdose rules tl;dr, pick two drugs that don't buff the same thing. Kamikaze plus Betameth for example. Or Psyche / Novacoke or Psyche / Cram. I like two long acting drugs you can pop early and just coast on, but Betameth plus Kamikaze is really the top performance, but you've got to juggle some non-trivial crash damage.
Body and Nephritic Screens add to addiction tests, but reduce the duration. I like Body 3 on the Juicer types to keep the long duration stuff running for a good long while.
Once you pick your two drug cocktail, take a Minor Addiction to them to get the +2 Dice to Addiction tests for those two Drugs. Willpower 3 plus Narco puts you to 5 Dice for Addiction tests, then add either Body or Logic depending on the Addiction type so with just 3's for Body/Logic/Willpower you can be at 8 dice and with Pharmaceutical or Designer grade you can keep it to Threshold 2 or less. If you squeeze in Drug Tolerant quality and drag Willpower up to 5 you've got 12 dice for your preferred Addiction tests and 8 for when you try new things. IMO 12 dice to get 2 hits is a bit of overkill.
