Meparfynol is a tertiary hexanol and potent tranquilizer with hypnotic/sedative and anticonvulsant effects and exceptionally low therapeutic index. It was discovered by Bayer in 1913 and was used shortly thereafter for the treatment of insomnia, but its use was quickly phased out in response to newer drugs with far more favorable safety profiles. Meparfynol depresses monosynaptic and polysynaptic reflexes and exerted weak ganglion and neuromuscular blocking actions. Meparfynol also produces transitory hypotension, an increase of aortic blood flow. Perfusion of the coronary arteries with Meparfynol led to a slowing of the heart, diminished systolic amplitude, dysrhythmias, and increased coronary flow. Respiration was stimulated with small and depressed with larger doses of Meparfynol.