Symptoms and Signs Acute Organophosphates and carbamates cause cholinergic symptoms due to activation of both major cholinergic receptors, which are characterized as muscarinic and nicotinic: Muscarinic cholinergic symptoms: Salivation, lacrimation, urination, defecation, vomiting, pinpoint pupils (miosis), bronchorrhea and wheezing, bradycardia Nicotinic cholinergic symptoms: Mydriasis, tachycardia, weakness and fasciculations, sweating, abdominal pain Of these manifestations, muscle fasciculations and weakness are typical.