Codeine: An opioid analgesic related to MORPHINE but with less potent analgesic properties and mild sedative effects. It also acts centrally to suppress cough.Antitussive Agents: Agents that suppress cough. They act centrally on the medullary cough center. EXPECTORANTS, also used in the treatment of cough, act locally.Morphine Derivatives: Analogs or derivatives of morphine.Hydrocodone: Narcotic analgesic related to CODEINE, but more potent and more addicting by weight. It is used also as cough suppressant.Substance Abuse Detection: Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.Narcotics: Agents that induce NARCOSIS. Narcotics include agents that cause somnolence or induced sleep (STUPOR); natural or synthetic derivatives of OPIUM or MORPHINE or any substance that has such effects. They are potent inducers of ANALGESIA and OPIOID-RELATED DISORDERS.Morphine: The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Nalorphine: A narcotic antagonist with some agonist properties. It is an antagonist at mu opioid receptors and an agonist at kappa opioid receptors. Given alone it produces a broad spectrum of unpleasant effects and it is considered to be clinically obsolete.Papaver: A genus of Eurasian herbaceous plants, the poppies (family PAPAVERACEAE of the dicotyledon class Magnoliopsida), that yield OPIUM from the latex of the unripe seed pods.Dealkylation: The removing of alkyl groups from a compound. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Analgesics, Opioid: Compounds with activity like OPIATE ALKALOIDS, acting at OPIOID RECEPTORS. Properties include induction of ANALGESIA or NARCOSIS.Hydromorphone: An opioid analgesic made from MORPHINE and used mainly as an analgesic. It has a shorter duration of action than morphine.Opium: The air-dried exudate from the unripe seed capsule of the opium poppy, Papaver somniferum, or its variant, P. album. It contains a number of alkaloids, but only a few - MORPHINE; CODEINE; and PAPAVERINE - have clinical significance. Opium has been used as an analgesic, antitussive, antidiarrheal, and antispasmodic.Debrisoquin: An adrenergic neuron-blocking drug similar in effects to GUANETHIDINE. It is also noteworthy in being a substrate for a polymorphic cytochrome P-450 enzyme. Persons with certain isoforms of this enzyme are unable to properly metabolize this and many other clinically important drugs. They are commonly referred to as having a debrisoquin 4-hydroxylase polymorphism.Dextropropoxyphene: A narcotic analgesic structurally related to METHADONE. Only the dextro-isomer has an analgesic effect; the levo-isomer appears to exert an antitussive effect.Cytochrome P-450 CYP2D6: A cytochrome P450 enzyme that catalyzes the hydroxylation of many drugs and environmental chemicals, such as DEBRISOQUINE; ADRENERGIC RECEPTOR ANTAGONISTS; and TRICYCLIC ANTIDEPRESSANTS. This enzyme is deficient in up to 10 percent of the Caucasian population.Ethylmorphine: A narcotic analgesic and antitussive. It is metabolized in the liver by ETHYLMORPHINE-N-DEMETHYLASE and used as an indicator of liver function.Oxymorphone: An opioid analgesic with actions and uses similar to those of MORPHINE, apart from an absence of cough suppressant activity. It is used in the treatment of moderate to severe pain, including pain in obstetrics. It may also be used as an adjunct to anesthesia. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1092)Cough: A sudden, audible expulsion of air from the lungs through a partially closed glottis, preceded by inhalation. It is a protective response that serves to clear the trachea, bronchi, and/or lungs of irritants and secretions, or to prevent aspiration of foreign materials into the lungs.Diphenoxylate: A MEPERIDINE congener used as an antidiarrheal, usually in combination with ATROPINE. At high doses, it acts like morphine. Its unesterified metabolite difenoxin has similar properties and is used similarly. It has little or no analgesic activity.Oxycodone: A semisynthetic derivative of CODEINE.Dextromethorphan: Methyl analog of DEXTRORPHAN that shows high affinity binding to several regions of the brain, including the medullary cough center. This compound is an NMDA receptor antagonist (RECEPTORS, N-METHYL-D-ASPARTATE) and acts as a non-competitive channel blocker. It is one of the widely used ANTITUSSIVES, and is also used to study the involvement of glutamate receptors in neurotoxicity.