When I am at work during the day I don’t have any opportunity to do any drawing, but there is sometimes enough time to read Fringe episode transcripts. How many times did Walter talk about, and/or do, drugs? It turns out that there were 51 mentions of specific drugs, or on-screen occasions of drug use, during Fringe’s five seasons. These drugs fall into the broad categories seen in this infographic.
Surprisingly, Walter’s favorite family of drugs appear to be sedatives. His second favorite category are hallucinogens, especially LSD, and he has dabbled a little bit in opiates. Walter absolutely does not go for stimulants of any kind, such as amphetamines or even caffeine derivatives (although he drinks coffee, not included in this infographic), and only mentioned cocaine once, and not in the context of having used it himself.
(As for references such as “spending hours spent ripped out of my gourd listening to Beatles albums backwards for secret messages,” those went under Miscellaneous Drugs.)