Remember that a chemical gland has to have a single natural, non-synthetic compound. Gamma-scopolamine is a synthetic created by combining two naturally occurring compounds, IIRC. (Something like gamma-vinyl-GABA and scopolamine. You get into unpronounceable chemical names FAST when you go into biochem.) This is part of the reason I've never cared much for them, as all the really good poisons or drugs are synthetics. However, if the chemical reservoir cyberware is still around, you could get that, and have it set to coat a cyberweapon when it first extends. That cyberware holds whatever you want, but you have to refill it. Which means you could dose your handrazors with Laes or Slab if you liked, which is a good way to end a fight quickly.