Overview:
Drugs are any synthetic or natural substances used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well-being. [1] Drugs can be everyday substances (caffeine, nicotine, ethyl alcohol) ; illicit substances (cannabis, heroin, cocaine) and food additives. [2] The study of drugs – what they are, how they work and what they do – is called Pharmacology.
Pharmacology comprises of:
• Pharmacodynamics-what a drug does to the body (includes biological effects and mechanism of action)
• Pharmacokinetics- what the body does to a drug(includes absorption, distribution, metabolism and excretion of drugs and their metabolites)
The most common ways in which a drug can produce its effects are shown in Fig.2. [3] Drugs that enter the body stimulate certain receptors, ion channels act on enzymes or transporter proteins.
• Agonists – chemicals or drugs that activate receptors and produce a response. Agonists activate receptors for endogenous mediators –e.g. Salbutamol is an agonist β2 adrenoreceptors. The after effect may be excitatory (e.g. increased heart rate) or inhibitory (e.g. relaxation of airway smooth muscle). Agonists at nicotinic acetylcholine receptors exert an inhibitory effect causing long-lasting depolarization at the neuromuscular junction and hence inactivation of the Na+ channels that initiate the action potential. Agonists possess affinity and efficacy.
• Antagonists – chemicals that combine with the receptor and block the action of the transmitter substance. Neutral antagonists block the effect of the agonist. There are two types of antagonism – Competitive (reversible and surmountable) and non-competitive (irreversible and insurmountable). Competitive a...
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[14] Hernández F, Avila J. Tauopathies. Cell. Mol. Life Sci.. 2007;64(17):2219–33. doi:10.1007/s00018-007-7220-x
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[16] Lanni C, Lenzken SC, Pascale A, et al. (March 2008). "Cognition enhancers between treating and doping the mind". Pharmacol. Res. 57 (3): 196–213.doi:10.1016/j.phrs.2008.02.004. PMID 18353672.
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[18] BBC online survey on Modafinil. Available from - http://www.dailymail.co.uk/health/article-2451586/More-students-turning-cognitive-enhancing-drug-Modafinil-hope-boosting-grades-job-prospects.html
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1. Administration is the route by which the drug or chemical enters the body. Routes of administration are classified as oral, topical, parenteral, rectal, or through inhalation. Absorption of drugs is dependent on how they are administered. Drugs that are taken orally have a slower onset of action compared to drugs taken parenterally (i.e. intravascular, intramuscular, or subcutaneous). Drugs of abuse that are taken by intravascular route such as cocaine or heroin, are absorbed within seconds of injection and result in immediate high. Drugs that are taken by oral route such as phenobarbital will have to be absorbed by the small intestines before effects of drug are seen.
Psychoactive drugs are classified into five different groups depending on how they affect the brain. In this essay I will be looking at three of these groups: stimulants, depressants and hallucinogens and how they exert influence on neural processing.
Sessa, B. "Is It Time to Revisit the Role of Psychedelic Drugs in Enhancing Human
Throughout the history of the human species, we have been always wanted to know three basic questions: why we are here, where did we come from, and where do we go after this life? Whether we were created from an omnipotent being as in many religions, we happened by chance and made it to where we are through evolution, or maybe even something else. Whatever the case may be, humans have always been curious and wondered about our existence and consciousness. Along with these age old questions, also came the use of psychoactive drugs and other mind altering substances. In order to try to understand these questions, humans have experimented with drugs that alter their state of consciousness.
Depression. Alzheimer’s. Autism. Stroke. Each of these words correlates with negative connotations. They afflict the mind, snatching away members of society like a ghost in the wind, leaving empty, damaged shells in their wake. Days drag into a dull grey blur, mental capacities weakening with each moment. For decades, medical researchers, working tireless hours with stark determination, have committed themselves to finding the cures to these and many more diseases that affect the brain. These scientists leapt over obstacles, ducking under impossibilities to see the clear picture, the clear goal. They refused to stop before discovering treatments that took the form of chemical drugs. Despite this, these treatments come riddled with side effects, strong chemicals alleviating some symptoms while bringing more into play. So research continued. Now, repetitive transcranial magnetic stimulation (rTMS) has risen as a potential treatment for various mental disorders. Although many chemical drugs have spelled relief for countless victims of depression and bipolar disorder, repetitive transcranial magnetic stimulation stands strong as the most effective treatment for mental disorders because of its influential effect on multiple disorders, minimal display of side effects, low potential for weaponization, and high capacity to surpass chemical drugs.
“Pharmacokinetics (PK) and pharmacodynamics (PD) can be seen as two sides of the same coin. PK and PD have a definite relationship, assessing how much drug gets to the site of action and then what that action is. Both activities are essential in the complete investigation of the interaction between the drug and body, and play significant roles in both drug development and their continual use in the clinical setting (Institute Of Clinical Research, Clinical Pharmacology Special Interest Group, Pharmacokinetics vs. Pharmacodynamics).”
...ibility with a wide range of experts and primary sources that the reader identifies as believable. As the reader Dyck compiled her knowledge and that of others that I was easily able to identify as key points to stress. She uses proper flow to organize a well balanced and exciting amount of sources that interest the reader and capture their attention to spread Dyck’s claims. She writes her historical novel based on solidifying themes and arguments with extensive sources that makes her claims hard to dismiss. Already I’ve researched other medical therapies using other sensitive illegal substances marijuana, MDMA, and cocaine that may be on breakthroughs of Alzheimer's, Parkinson's, and cancer related diseases. Maybe more funding should be invested in this research to better gain understanding and awareness of the possible valuable advances that these drugs may offer.
The altered states of consciousness produced by drugs presents an all-to-common phenomenon in today’s society. Whether the desired sensation comes in the form of energy, a means of relaxation, or pain reduction, many people go to great lengths and present their bodies to threatening conditions in order to achieve this euphoric “high.” Unfortunately, the use of these drugs very often comes with dangerous side effects that users must learn to manage with for the rest of their life. According to neuroscientists, our entire conscious existence bases itself off of the lighting-fast reactions occurring in our nervous system (Nichols, 2012). Therefore, changing these neurological reactions can permanently effect our conscious being (Blatter, 2012). The physical and neurological effects from the use and abuse of stimulants, sedatives, hallucinogens, organic solvents, and athletic performance enhancing drugs will be discussed in order to better comprehend why certain individuals expose themselves to such dangerous materials with seemingly no regard to the permanent consequences associated with such actions.
The mind is a powerful tool. It can be used to heal or harm the body. The body does not have to be physically treated with medicines and treatment, or be physically harmed because the mental power of the mind can make physical changes within the body on its own. The placebo effect is a beneficial effect that can make physical changes inside of the body solely based on the power of the mind and the belief that you are going to get better. The adverse effect that also uses the strength of the mind is the nocebo effect. The nocebo effect is just the same as the placebo effect except that it generates the opposite results of the placebo effect and harms the body.
Reasons for using drugs depend on the type of substance being taken. Two common examples of widely abused drugs are marijuana and cocaine. Since both of these have different effects, the individual will likely take the drug that can best resolve their problems or needs.
Drugs are chemicals that change the way a person's body or mind works. Drugs are not good for health as they have many side effects and damage our brain, heart and other important organs. Drug is a depressant that slows down the functions of the central nervous system and makes us less aware of the events around us. I...