A case report of an urban family who experienced excessive exposure to organophosphate and carbamate pesticides is presented. All three family members developed symptoms that were compatible with cholinesterase inhibition: headache, lightheadedness, wheezing, shortness of breath, nausea, and fatigue. Serial measurement of red blood cell and serum cholinesterases soon after exposure and during subsequent months confirmed the diagnosis of pesticide poisoning. This report demonstrates that the misapplication of pesticides commonly used in residences in urban areas can cause acute pesticide poisoning and demonstrates the usefulness of repeated measurements of cholinesterase during the post-exposure period in establishing the correct diagnosis.