sympathomimetic /sim′pəthō′mimet″ik/ [Gk, sympathein + mimesis, imitation] , a pharmacological agent that mimics the effects of stimulation of organs and structures by the sympathetic nervous system. It functions by occupying adrenergic receptor sites and acting as an agonist or by increasing the release of the neurotransmitter norepinephrine at postganglionic nerve endings. Various sympathomimetic agents are used as decongestants of nasal and ocular mucosa, such as bronchodilators in the treatment of asthma and vasopressors and cardiac stimulants in the treatment of acute hypotension and shock; they are also used for maintaining normal blood pressure during operations using spinal anesthesia. Drugs in this group include cyclopentamine, DOBUTamine, DOPamine, epHEDrine, isoproterenol, metaproterenol, metaraminol, mephentermine, methoxamine, methoxyphenamine, naphazoline, norepinephrine, phenylephrine, propylhexedrine, protokylol, pseudoephedrine, terbutaline sulfate, tetrahydrozoline, tuaminoheptane, xylometazoline, and epINEPHrine, a synthetic isomer of the hormone secreted by the adrenal medulla. Adverse effects of sympathomimetic drugs may be nervousness, severe headache, anxiety, vertigo, nausea, vomiting, dilated pupils, glycosuria, and dysuria. Also called adrenergic drug.
