TYPICAL USAGE Pain of hypersensitive teeth. SIDE EFFECTS Vertigo, headache, hypotension, convulsions, cyanosis, GI disturbance, collapse, flushing of the skin, irregular pulse, methemoglobinemia. DRUG INTERACTION Tell your doctor of all prescription and nonprescription medication you may use. Do not start or stop any medicine without doctor or pharmacist approval. MECHANISM OF ACTION The potassium ions in potassium nitrate desensitizing products are work by blocking the synapse between nerve cells, reducing nerve excitation, and the associated pain.