We were never given any instruction on the purpose of the strange Latin named substances.
Whether they stopped you having the sh*ts, purified water, stopped wound infection or killed pain, we hadn't a clue.
Despite being asked several times for simple instructions to be included, the Rubber Queens of Mountbatten were more interested in trying to scare you about conduct after capture (The Big Six - Name, Rank, Number, Aircraft, Weapon, Target) than in giving any practical briefs on the medicinal contents of the PSP.