Quick Spores
Derived from a fungus, the spores react when they come into contact with moisture with explosive growth. Used by government and corporate security in the form of grenades; also used by the Punisher 2099.
Quote: "It reacts with the lining of the lungs, tear ducts, and other moist places."
Punisher 2099 #4

Rapture
A highly addictive drug legally manufactured by Alchemax, who are also the only place to legally purchase the drug.
Rapture bonds to the user on a genetic level, so a single use is all it takes to become addicted.
It has particularly nasty withdrawal symptoms.
 
Rapture is important to continuity as it played a key role in the origin of Spider-Man 2099.
Miguel O'Hara's boss at Alchemax, worried about O'Hara quitting, slipped the drug in his drink so he would have to stay at Alchemax.
O'Hara used his gene therapy expertise to rewrite his genetic code to get rid of the Rapture addiction, but one of his coworkers sabotaged the machine, and this is what led to him gaining him his spider powers as Spider-Man 2099.
A later issue did slightly retcon the origin, but 'm sticking with the original story.
Spider-Man 2099 #1, #2

Recombinant Toad Venom
A street drug available in the markets of the Little Calcutta neighborhood in Transverse City.
The effects of the drug are never mentioned.
Ghost Rider 2099 #9

Restorative Cream
An over-the-counter cream that heals mild injuries, such as bruises.
Spider-Man 2099 #9

Rhapsody
An addictive euphoric and relaxation drug available on the black market.
In addition to its illicit street use, Rhapsody is also used by the Synthia corporation, which adds a derivative of the drug to their pseudo-steak in an effort to keep the population docile.
Slang: Users of the drug are called "rhapsody heads."
X-Men 2099 #6, #16