Quick Answer. The function of a synaptic knob is to change the action potential that is carried by axons into a chemical message. The chemical message then interacts with the recipient neuron or effector. This process is called synaptic transmission.
Over-the-counter (OTC) medicines that are recommended for head or pubic lice include: 1  Permethrin creme rinse 1% (such as Nix), which is a common first choice for treating head lice. 2  Shampoos containing pyrethrins and piperonyl butoxide (such as Rid), which are left on the hair for 10 minutes and then rinsed out.
Permethrin is a common synthetic chemical, widely used as an insecticide, acaricide, and insect repellent. It belongs to the family of synthetic chemicals called pyrethroids and functions as a neurotoxin, affecting neuron membranes by prolonging sodium channel activation.ermethrin is available for topical use as a cream or lotion. It is indicated for the treatment and prevention in exposed individuals of head lice (Pediculus humanus capitis) and treatment of scabies (Sarcoptes scabies).