hi! the apo in the group i'm DMing want to make some sort of combat drug (mainly for himsef)

even if this could be canon breaking, makeing one player happy is more important to me.

the core rulebook only have pain suppressant, wich come included in the power armor.

i like to create one drug for each of the space marine organ. said drug temporary enhance it's function.

to limit them i was planning to add some cost on requisition, and disallow multiple use on each SM, without a period to detoxify.

do someone made something similar? is there something in the lore of WH40k?

The Emperor's Children used a lot of drugs in and out of combat. The World Eaters used something like Frenzon as well, but its pretty easy to tell how well that went. I haven't heard any canon where Imperial chapters use drugs to increase combat effectiveness.