If you need to have any type of surgery, tell the surgeon ahead of time that you are taking pyridostigmine. Based on the animal studies, it is thought that any potential benefits from use of PB mista voin ostaa pyridostigmine occur only if: It is taken within hours before, but not right before, exposure to the nerve agent Soman. This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Other less serious side effects are more likely to occur, such as: sweating or urinating more than drooling, watery warmth or tingly mild nausea, vomiting, or stomach mild itching or skin or muscle or joint pain. It is very hard to tell the difference between too little and too much pyridostigmine.