Symphytroph, also known as pymphothion, is a non-systemic organophosphorus insecticide that is particularly effective against dipteran pests. It is also used to control ectoparasites and has significant effects on skin flies. It is effective for humans and livestock. Highly toxic. It can reduce the activity of cholinesterase in whole blood, causing headache, dizziness, irritability, nausea, vomiting, sweating, salivation, miosis, convulsions, dyspnea, cyanosis. In severe cases, it is often accompanied by pulmonary edema and cerebral edema, which can lead to death. In respiratory failure.