Drug discovery crude preparations are morphine, the active agent in opium, and digoxin, a heart stimulant originating from Digitalis lanata. Organic chemistry also led to the synthesis of many of the natural products isolated from biological sources. Historically, substances, whether crude extracts or purified chemicals, were screened for biological activity without knowledge of the biological target. Only after an active substance was identified was an effort made to identify the target. This approach is known as classical pharmacology, forward pharmacology, or phenotypic drug discovery. Later, small molecules were synthesized to specifically target a known physiological/pathological pathway, avoiding the mass screening of banks
Cannabis (drug) Cannabis (drug) Cannabis, also known as marijuana among other names, is a psychoactive drug from the "Cannabis" plant used for medical or recreational purposes. The main psychoactive part of cannabis is tetrahydrocannabinol (THC), one of 483 known compounds in the plant, including at least 65 other cannabinoids. Cannabis can be used by smoking, vaporizing, within food, or as an extract. Cannabis has mental and physical effects, such as creating a "high" or "stoned" feeling, a general change in perception, heightened mood, and an increase in appetite. Onset of effects is within minutes when smoked, and about 30 to 60 minutes