Opiate is a term classically used in pharmacology to mean a drug derived from opium. Opioid, a more modern term, is used to designate all substances, both natural and synthetic, that bind to opioid receptors in the brain. Opiates are alkaloid compounds found in the opium poppy plant Papaver somniferum; the psychoactive compounds found in the opium plant include morphine and thebaine. Opiates are considered drugs with moderate to high abuse potential and are listed on various "Substance-Control Schedules" under the Uniform Controlled Substances Act of the United States of America. In 2014, between 13 and 20 million people used opiates recreationally. Opiates belong to the large biosynthetic group of benzylisoquinoline alkaloids, are so named because they are occurring alkaloids found in the opium poppy; the major psychoactive opiates are morphine and thebaine. Papaverine, 24 other alkaloids are present in opium but have little to no effect on the human central nervous system, as such are not considered to be opiates.
Small quantities of hydrocodone and hydromorphone are detected in assays of opium on rare occasions. Dihydrocodeine, oxycodone, oxymorphone and other derivatives of morphine and/or hydromorphone are found in trace amounts in opium. Despite morphine being the most medically significant opiate, larger quantities of codeine are consumed medically, most of it synthesized from morphine. Codeine has more predictable oral bioavailability, making it easier to titrate the dose. Codeine has less abuse potential than morphine, because it is milder, larger doses of codeine are required. Opiate withdrawal syndrome effects are associated with the abrupt cessation or reduction of prolonged opiate usage. While the full synthesis of opioids from naphthoquinone or other simple organic starting materials is possible, they are tedious and uneconomical processes. Therefore, most of the opiate-type analgesics in use today are either extracted from Papaver somniferum or synthesized from those opiates thebaine. In 2015 researches reported successful biosynthesis of thebaine and hydrocodone using genetically modified yeast.
Once scaled for commercial use the process would cut production time from a year to several days and could reduce costs by 90%. Heroin is one of several semi-synthetic opioids derived from the morphine. Although sometimes not considered opiates, as they are not directly derived from natural opium, they are referred to as opiates. Heroin is a morphine prodrug. One of the major metabolites of heroin, 6-monoacetylmorphine, is a morphine prodrug. Nicomorphine, dipropanoylmorphine, methyldesorphine, acetylpropionylmorphine, dibenzoylmorphine, diacetyldihydromorphine, several others are derived from morphine. Opiate comparison Opioid epidemic World Health Organization guidelines for the availability and accessibility of controlled substances
Pharmacology is the branch of biology concerned with the study of drug action, where a drug can be broadly defined as any man-made, natural, or endogenous molecule which exerts a biochemical or physiological effect on the cell, organ, or organism. More it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function. If substances have medicinal properties, they are considered pharmaceuticals; the field encompasses drug composition and properties and drug design and cellular mechanisms, organ/systems mechanisms, signal transduction/cellular communication, molecular diagnostics, toxicology, chemical biology and medical applications and antipathogenic capabilities. The two main areas of pharmacology are pharmacokinetics. Pharmacodynamics studies the effects of a drug on biological systems, Pharmacokinetics studies the effects of biological systems on a drug. In broad terms, pharmacodynamics discusses the chemicals with biological receptors, pharmacokinetics discusses the absorption, distribution and excretion of chemicals from the biological systems.
Pharmacology is not synonymous with pharmacy and the two terms are confused. Pharmacology, a biomedical science, deals with the research and characterization of chemicals which show biological effects and the elucidation of cellular and organismal function in relation to these chemicals. In contrast, pharmacy, a health services profession, is concerned with application of the principles learned from pharmacology in its clinical settings. In either field, the primary contrast between the two are their distinctions between direct-patient care, for pharmacy practice, the science-oriented research field, driven by pharmacology; the origins of clinical pharmacology date back to the Middle Ages in Avicenna's The Canon of Medicine, Peter of Spain's Commentary on Isaac, John of St Amand's Commentary on the Antedotary of Nicholas. Clinical pharmacology owes much of its foundation to the work of William Withering. Pharmacology as a scientific discipline did not further advance until the mid-19th century amid the great biomedical resurgence of that period.
Before the second half of the nineteenth century, the remarkable potency and specificity of the actions of drugs such as morphine and digitalis were explained vaguely and with reference to extraordinary chemical powers and affinities to certain organs or tissues. The first pharmacology department was set up by Rudolf Buchheim in 1847, in recognition of the need to understand how therapeutic drugs and poisons produced their effects. Early pharmacologists focused on natural substances plant extracts. Pharmacology developed in the 19th century as a biomedical science that applied the principles of scientific experimentation to therapeutic contexts. Today pharmacologists use genetics, molecular biology and other advanced tools to transform information about molecular mechanisms and targets into therapies directed against disease, defects or pathogens, create methods for preventative care and personalized medicine; the word "pharmacology" is derived from Greek φάρμακον, pharmakon, "drug, spell" and -λογία, -logia "study of", "knowledge of".
The discipline of pharmacology can be divided into many sub disciplines each with a specific focus. Clinical pharmacology is the basic science of pharmacology with an added focus on the application of pharmacological principles and methods in the medical clinic and towards patient care and outcomes. Neuropharmacology is the study of the effects of medication on central and peripheral nervous system functioning. Psychopharmacology known as behavioral pharmacology, is the study of the effects of medication on the psyche, observing changed behaviors of the body and mind, how molecular events are manifest in a measurable behavioral form. Psychopharmacology is an interdisciplinary field which studies behavioral effects of psychoactive drugs, it incorporates approaches and techniques from neuropharmacology, animal behavior and behavioral neuroscience, is interested in the behavioral and neurobiological mechanisms of action of psychoactive drugs. Another goal of behavioral pharmacology is to develop animal behavioral models to screen chemical compounds with therapeutic potentials.
People in this field use small animals to study psychotherapeutic drugs such as antipsychotics and anxiolytics, drugs of abuse such as nicotine and methamphetamine. Ethopharmacology is a term, in use since the 1960s and derives from the Greek word ἦθος ethos meaning character and "pharmacology" the study of drug actions and mechanism. Cardiovascular pharmacology is the study of the effects of drugs on the entire cardiovascular system, including the heart and blood vessels. Pharmacogenetics is clinical testing of genetic variation that gives rise to differing response to drugs. Pharmacogenomics is the application of genomic technologies to drug discovery and further characterization of older drugs. Pharmacoepidemiology is the study of the effects of drugs in large numbers of people. Safety pharmacology specialises in detecting and investigating potential undesirable pharmacodynamic effects of new chemical entities on physiological functions in relation to exposure in the therapeutic range and above.
Systems pharmacology is