an opium alkaloid initially isolated in the 1840s. It has no psychopharmacological function but is a potent vasodilator, being utilized in the remediation of angina pectoris once in awhile, to escalate blood flow within the cerebral arteries, or, whenever delivered into the corpora cavernosa of the penis, to generate erection in the management of impotence. U.S. brand name: Para-Time S.R.