1-[(1R)-1-Phenylethyl]-1H-imidazole-5-carboxylic Acid Ethyl Ester; Amidate; Hypnomidate; R-16659

Etomidate is a potent, non-competitive, centrally acting α-adrenergic receptor agonist that has been used as a diagnostic agent and anesthetic. It is also used in the treatment of diabetic neuropathy. Etomidate binds to the α-adrenergic receptors on the presynaptic membrane and blocks the release of norepinephrine. This prevents nerve impulses from being transmitted to the muscle cells, leading to relaxation of muscles. Etomidate also inhibits locomotor activity by inhibiting postsynaptic neurons in the spinal cord that are responsive to acetylcholine. Etomidate is not active against polymorphonuclear leucocytes or water vapor. The risk group for etomidate includes patients who have had intubations, those with systolic pressures greater than 120 mmHg, and those with heart rates greater than 100 beats per minute. The mechanism of action for etomidate is thought to be through formation of stable complexes with nitrogen atoms.