BioShield is powered by NeuroRX. NeuroRX works by attacking a neurotransmitter found only in insects. Neurotransmitters control the heart rate and metabolism. Fleas, ticks, mosquitoes and bed bugs produce a neurotransmitter called octopamine. NeuroRX blocks the octopamine, causing a complete shutdown of the central nervous system killing insects nearly instantaneously. NeuroRX is safe to use around children and pets but is deadly to insects when used as directed. Deadly to insects. Safe around children and pets.