Medicines and drugs Essay

A do do do medicatesss or medicine is a chemical substance that alters incoming sensory sensations, vagary or emotions, or physiological state.Paink disappointmenters, hallucinogens and alcoholic beverages be examples of drugs and medicines that alter incoming sensory sensations. fluoxetine and alcohol alter modal value or emotionsSteroids, cig arttes and meat medicines alter physiological state, including consciousness, activity level or coordination.Drugs such as antiseptics, antibiotics and antivirals be infection fighters hormones and vitamins expunge body alchemy or metabolism stimulants, depressants, analgesics and anesthetics affect the underlying nervous system and the outlook.It is akinwise grave to understand that the human body has great natural better processes some drugs just increase the rate of natural healing.Also, there could be a placebo effect, it is when a pharmacologically inert substance that make seems to service of process beca utilize the p erson taking the substance was told that it would work.Placebo effect is ex aminoalkaned by giving lollipop pills to one group of tests patients, and real drugs to a nonher group (when they ar not aw be of which they receive).B.1.2 Outline the stages involved in research, development and testing of advanced pharmaceutical products.This precedes a truly long time and costs a fortune, and is often controlled by the government. Before drugs argon tested on humans, they mustiness be testing on various animal(prenominal)s (start with infinitesimal animals and then go to bigger ones).The range of effective doses, the doses in which placement-personal set up arise and the fatal doses take up to be de confinesined.There are 3 phases then clinical running play clinical evaluation (to a greater extent in depth analysis) human studies with to a greater extent evaluation, really few drugs make it to the market, and the development would have cost a lot.sometimes, things evict eq uable go wrong, like Thalidomide. It was given to pregnant women to contend daysp coterie sickness, but it cause deformities in babies Now it is still use, but to diplomacy fur sores.B.1.3. identify the disagreeent methods of administering drugs* Oral Very convenient. yet, it efficiencyiness not be bona fide as the rate of absorption depends on drug dousing, endure content and pH value. As most is absorbed in the small intestines, so the drug must survive the gastric irate. and so it often lays in time release capsules.* Rectal Good when drug ordurenot be taken orally due to vomiting or because the drug is pH sensitive.* Inhalation Rapid, as there are loads of parenthood vessels in the lungs, and indeed a drug would have a reli fit effect. Good for general anaesthesia, and asthma medicine.* Parentalo Just downstairs the skin s first-class honours degreeer than for intravenous. Used often for dental injectionso Into muscles for extensive doses, or when immediate res ponse is not needed (vaccines etceteratera.o intravenous almost instantaneous, but sack upnot be un seizee when injectedFatty lipids whitethorn bandage some kinds of drugs, so the drugs wont leave the body so fastThe half(a) life of a drug is the time for half the dose in the body to be eliminated.B.1.4. hold forth the verges lethal venereal disease (LD50), tolerance and side personal effects.LD50 is the lethal dose for 50% of the existence and it varies a lot from drug to drug.When one is tolerant, then one has to take a larger dose in order to disembodied spirit the precious effects.Some people after often use of a drug becomes dependant on it physically (they must have it to be able to fit physically) or mentally (they must have it to feel right). permissiveness doesnt necessarily mean that one gets apply to the wounding effects.Sometimes it is hard to know the difference between main effect and side effect. A drug has umteen effects, and some patients benefit fr om a few of those effects then those are the main effects, and all the an other(a)(prenominal) are side effects. Someone else, with another disease whitethorn benefit from other effects, and then those become the main effects. There are al slipway harmful effects too.The risk benefit ratio should excessively be considered.B.2.1. arouse and explain how excess corrosiveity in the stomach can be reduced by the use of different bases.Bases, most often alloy oxides, hydroxides, carbonates or hydrogen carbonates are used as ant window panes. These react with acid in the stomach to adjust the pH value.The purpose of gastric acid is to kill off bacterium, and help in digestion. save, over-eating or stress stimulates more production of acid, causing discomfort.The active ingredients tend to be this react scarce with HClMagnesium OxideMagnesium HydroxideAluminium HydroxideCalcium carbonateSodium Hydrogen CarbonateMagnesium TrisilicateSome of the products Carbon dioxide is a gas. So a foaming agent has to be added to prohibit prodigal belching. Also alginates are used, to prevent acid reflux.If too much antacid is used, the stomach becomes too basic, and that hurts too then more antacid cleverness be wrongly taken. This fartings to alkalosis.B.3.2. Describe the use of derivatives of salicylic acid as diffuse analgesics and compare the advantages and disadvantages of using aspirin and paracetamol (acetaminophen)Salicylic acid is used as an anti-pyretic (fever reducer) and nutty analgesic (painkiller), but it is a strong acid and hurts the stomach and blab so variations of salicylic acid was used. bingle is Acetyl Salicylic Acid (ASA) or Aspirin, which has the benefits of salicylic acid and does not irritate so much due to the acetyl group.When ASA reacts with water, it becomes salicylic acid, and the by-product of ethanoic acid.GOOD It is good for killing minor pain, reducing fever, acting as an anti-inflammatory agent and prevents abnormal argument clot .BAD Upsets stomach and exhaust allergy accidental poisoning in infants and Reyes syndrome.Acetaminophen is as well an anti-pyretic and analgesic. However it does not upset the stomach and is safe. However, overdose can still occur and lead to liver and brain damage. And it is not anti-inflammatory.Ibuprofen is like aspirin and cause fewer stomach problems. It is anti-inflammatory and is very safe.B.3.3. equivalence the structures of morphine, codeine and the semi-synthetic opiate heroin.These are strong analgesics and are often called opiates, narcotics or narcotic analgesics. The study pain relieving substance originates from the opium poppy plant is sleep inducing and pain relieving. in all three share the aforementioned(prenominal) skeleton. Remember the group C2H3O2 is called an acetyl group.B.3.4. question the advantages and disadvantages of using morphine and its derivatives as strong analgesics.These affects The Central Nervous System, the center and the Gastrointest inal tract (the digestive system)They are used as virile analgesics (severe pain from injury and chronic diseases) treatment of diarrhoea, relieve coughing.However they are very addictive and are rather replaced with something else.They also produce mood changes, drowsiness and mental clouding.Tolerance can arise by alteration of the liver and neurons in the brain.Some people cant function without the drug, feeling restless(prenominal)ness, sweating, fever, chills, vomiting, aches etc due to abstinence of the drug.There is often severe psychological dependence too (one might feel extremely depressed).Short term effects Sedation, stupor, pain recess, euphoria, reduced tension, worry, couching reflex. unitary might die of overdose. abundant term effects Loss of appetite, sterility, withdrawal illness, crime, diversion of energy.B.4.1. Describe the effects of depressantsTranquilizers, sedatives and spellbindings, which calm and relax they slow down heart rate and breathing.Tranqui lizers accept alcohol, Valium and Librium and are weaker than the others. These relieve anxiety and tension.Sedatives Barbituates that soothe hurt without producing much sleep in small doses.Hypnotics Like chloral hydrate. These induce sleep. in addition much can lead to coma or teach.B.4.2. Discuss the well-disposed and physiological effects of the use and abuse of fermentation alcohol.Social effects major(ip) costs from alcohol are from sickness and death, as in infirmary treatments and lost efficiency. Property crimes and crimes against people drinking while driving.Physiological effects Harmful to comparisonships, and whitethorn physically or emotionally harm others. One whitethorn lose control and develop dependence and tolerance.It increases race rack when drinking and nausea, sweating and anxiety as withdrawal of use.Short-term effects CNS depressant reduces tension. It triggers Euphoria, Talkativeness, Dilation of linage vessels, Violent behaviours, Inertia, Coma, De ath. ache term effects Cirrhosis, liver cancer, coronary heart disease, high parenthood pressure, strokes, gastritis, low birth mass etc. alcoholic drink can be used for antiseptics such as mouthwashes.B.4.3. Describe and explain the techniques used for the detection of ethanol in the breath of in the melodic line or urine.Ethanol passes from the stomach into the blood and therefore it passes into the lungs and ethanol vapour is formed.The breathalyser test might involve a redox equation with potassium dichromate as oxidizing agent.Color change Red-Orange to GreenThe gas liquid chromatography works as follows Small samples of gases and volatile liquids such ethanol are let outd. These are pushed through a column using an unimportant gas, such as newton gas and different gases take different time to come to the detector, where concentration of gases are measured.Intoxilyzer, Infra-red spectroscopy Infra-red energy make molecules brood. Different types of bonds absorb and vibrat e at different infer-red frequencies. By measuring how much energy is not absorbed by the molecules, one can find the number of authentic bonds in the molecules.B.4.4. Describe the synergistic effects of ethanol with other drugs.Alcohol is easily absorbed in the stomach, so drugs that can be fade away in alcohol will be absorbed much quicker, and the dosage will seem higher as in normal conditions the liver removes a part of the drug. So performance of the drug is enhanced and may lead to devastating effects such as death, particularly if alcohol is unite with barbituates. Alcohol with aspirin increases the risk of stomach bleeding.B.4.5 . List other comm all used depressants and describe their structures.Valium (diazepam) is a tranquilizer, Mogadon (Nitrazepam) is a hypnotic drug (used to control seizures and infantile spasms), Prozac (hydrochloride) is an anti-depressant drug used to treat mental depression.Diazepam and Nitrazepam have similar carbon skeletons meanwhile Prozac is different.B.5.1. List the physiological effects of stimulants.Stimulants are chemicals that stimulate the brain and the central nervous system. It is the opposite of a depressant. These increase alertness. Examples are amphetamine, nicotine and caffeine.B.5.2. Compare amphetamines and epinephrineThey both derive from the phenylethylamine structure, and therefore look similar. Furthermore, amphetamines mimic the effects of adrenaline (they are sympathomimetic drugs), as they constrict arteries and thus increases sweat production. They increase heart rate, blood pressure, respiration and insomnia.Medical uses Treat mild depression, narcolepsy and asthma.They use up the bodys reserve energy and can lead to a collapse.B.5.3 Discuss the short- and long-term effects of nicotine consumption.Tobacco is a origin of nicotine which is a mild stimulant with a short lived effect. The response is followed by depression and thereby makes one pushed to use it more often.Short-term add in hea rt-rate and blood pressure. It constricts blood vessels and therefore strains the heart. Nicotine also reduces urine output.Long term effects of nicotine It stresses hard and may lead to heart diseases and blood clot May lead to increase of fatty acids in the blood. hummer leads to more carbon monoxide in the blood making the blood less able to carry blood. It also increases the gastric acid production and may lead to ulcer.Smoking causes Cancer in lungs and mouth heart and blood vessel disease breathing difficulties and chronic bronchitis air pollution fires disadvantageously teeth insomnia.B.5.4. Describe the effects of caffeine and compare its structure with that of nicotine. caffein stimulates the respiratory system (more energy is available from respiration), so heart and brain gets more energy. So one becomes more alert, motivated and well-being. In small amounts in is rather harmless, but too much causes insomnia. One gets more urine as well.Caffeine leads to some tolerance but no physical addiction. It can be given to babies to help their breathing. It also constricts blood vessels and therefore helps against migraines.Both caffeine and nicotine contain a tertiary amine group. Caffeine has more of those though.B.6.1. Describe the historical development of penicillins.In 1928, Fleming out of the blue saw that some types of fungi killed off a certain bacterium and started to try to isolate the fungi, but it was too hard to purify it. In 1940, Floray and Chain continued with penicillin testing and development, and in 1943 it was available clinically.The first penicillin was Penicillin G. However it was deactivated by stomach acid so it had to be injected. Acid oppositeness penicillins such as penicillin V was developed by modifying the side bondage of the basic penicillin structure. Some bacteria could deactivate penicillin G by synthesising an enzyme, therefore one had to make other synthetic penicillins. 6-APA penicillin is inert, but an extra ami no group H2N would activate it.B.6.2. Compare broad(a) spectrum and particularise spectrum antibioticsA broad spectrum antibiotics is effective against a wide variety of bacteria. Examples are tetracyclines.Narrow ones are effective only against certain types of bacteria most penicillins are narrow spectrum antibiotics.One often has to determine the bacterium before getting antibiotics, because a broad-spectrum one can kill beneficial bacteria and give discomfort.B.6.3. rationalise how penicillins work and discuss the effects of modifying the side chain.The cell walls of some bacteria are composed of polysaccharides, and these layers are supported by cross-links. However, penicillins interfere with the organization of these links and therefore weaken the structure. The bacteria can easily burst. Animals cells dont have these cell walls and are therefore not affected.It is important to modify the side chain to work against bacteria have evolved and are able to break down certain t ypes of penicillin. Side chains are also added to make the penicillin work (as for the 6-APA) and to survive the gastric acid (Penicillin G)B.6.4. Discuss and explain the effect over prescription of penicillins has, and the use of penicillins in animal feedstockRepeated use may lead to allergic reactions.They can also wipe out harmless and beneficial bacteria in the solid food canal, and harmful bacteria might eventually replace these.Bacteria can become resistant against certain antibiotics and then pass on their immunity.In feedstock They are used to kill dangerous pathogens which may otherwise scotch humans and animals. They are also used to increase productivity.However, this increases the chances that bacteria might become resistant.B.7.1. State how viruses differ from bacteriaBacteria are comparatively large single cell microorganism with DNA strands. Viruses are cell-free and are much smaller and are not living. They can only reproduce within a armament cell.B.7.2. Describ e the different ways in which antiviral drugs work* Block the transfer of genetic reading* Control by inoculation, vaccines.* Block the enzyme activity in a host cell, so that the virus cant use it to replicate.B.7.3. Discuss the difficulties associated with solution the AIDS problemHIV molecules bind to proteins on T-type of white blood cells and hinder them from fighting infections by inactivating them. HIV virus is good at mutating and together with their similarities with human cells, it is very heard to treat with antiviral drugs and vaccines.B.8.1. Describe the importance of geometrical isomerism in drug action.Stereoisomers are isomers with the same molecular formula and the same geomorphologic formula, but different arrangement of atoms in space.Geoemetric isomers have different physical properties such as polarity, boiling point, and solvability etc. They may also undergo different t chemical reactions although their functional groups are identical.For example cisplatin is en effective anti-cancer drug (as it may enter the nucleus of a cancerous cell), but the trans-isomers is inactive in such purposes.B.8.2. Discuss the importance of chirality in drug action. visual isomers differ from geometric isomers in cardinal ways* Optical isomers are chiral (asymmetric)* Optical isomers are non-superimposable mirror images of each otherOne optical isomer rotates the rag polarized lax one direction, meanwhile its other isomer rotates it the other way.An equi- bomber mixture of two enantiomers means a 50-50 ration and will not totate the plane of polarised light at all this is a racemic mixture.Penicillin V is active, but its enantiomer is inactive.One enantiomer of Thalidomide could be used to treat morning sickness in pregnant women and was marketed as a racemix mixture, but its other enantiomer gave fetal deformities.B.8.3. Describe the use of chiral auxiliaries to form the desired enantiomer.It is very heard to separate racemic mixtures into separate e nantiomers, as they have identical chemical properties in relation to non-chiral reagents. Instead, scientists use stereospecific synthesis to produce only one kind of enantiomer. Chiral auxiliaries are used to convert non-chiral molecules into a desired enantiomer by attching itself chemically to the non-chiral molecule so that only one type of enantiomer can be formed. After the procedure the auxiliary can be recycled. This is used when synthesising Taxol which isa drug effective against breast cancer.B.8.4. Explain the use of combinatorial chemistry to synthesise new drugs.This is when one creates lots of molecules and test them quickly for biologic properties one starts with a set of basic chemicals which are then combined in all possible combinations, and this allows a fast production of many different molecules, increasing the chance of finding better drugs.A library is a collection of compounds that are screened to determine their usefulness as a drug, using parallel synthe sis (identical processes with many different molecules at the same time).B.9.1. Compare local and general anaesthetics in terms of their modes of action local anaesthetic anaesthetics block the pain in specific areas when they are injected under the skin or used as a crme. Examples are cocaine, procaine, benzococaine, lidocaine etc. These block local nerve transmissions and decrease blood supply to that area. procaine and lidocaine do not affect the brain, meanwhile cocaine does.General anaesthetics affect the brain and produce unconsciousness. But it is easy to reverse the unconsciousness. Examples are azotic oxide, diethyl ether, chloroform, cyclopropane and halothane.B.9.2. Compare the structures and effects of cocaine, procaine and lidocaine.All three have the benzene ring and the tertiary amine.Cocaine also stimulates the central nervous system. It constricts blood vessels which leads to high blood pressure, and cant be safely used. Although it doesnt produce withdrawal symptom s and tolerance, it produces a strong psychological addiction. An overdose suppresses heart and respiration.Cocaine has a very short half life as it is metabolized by the liver fast, and is poorly absorbed when taken orally.Procaine gives extensive relief from pain which is good for surgery and dental procedures. It is non-toxic and non-irritant.Lidocaine is used locally to produce numbness. It is more potent that procaine, but may cause chunk and itching.B.9.3. Discuss the advantages and disadvantages of nitrous oxide, ethoxyethane, trichloromethane, cyclopropane and halothane.Nitrous oxide is not very potent, and makes one feel goodTrichloromethane is nonflammabe, but leads to liver redress. Narrow safety meteEthoxyethane alleviates the pain in surgery well, but it is very combustible and nonstable.Cyclopropane is a very potent anaesthetics, however it forms explosive mixtures with air and is very flammable. It also causes vomiting and nausea.Halothane is widely used as it is not flammable and one may recover fast from it. It doesnt irritate the respiratory tract. However, it takes time to become unconscious. It is potentially harmful to the ozone layer as it produces chlorine and bromine free radicals.B.9.4. Calculate the partial pressures of component gases in an anaesthetic mixtureThe partial pressure ratios of the total pressure equal the molar ratios of different gas molecules.It is important to have enough oxygen in the anaesthetic mixture so that the patient can live. At least 20% oxygen is neededB.10.1 Describe the effects of lysergic acid diethylamide (lysergic acid diethylamide), mescaline, psilocin and tetrahydrocannabinol.Psychadelic drugs like these alter the mind and produces a change in thought, percept or mood and induce vivid fantasies. Colors seem more brilliant for the user.There are the effects of the mentioned mind altering drugsLSD This is a powerful hallucinogen that strongly magnifies perception and may subvert the sense of j udgment. No physical addiction, and not very strong psychological dependence.Mescaline Color hallucinations which last 12 hours.Psilocybin Similar to LSD, especially at high doses, but at low doses produces relaxation. Shortlasting 4 hourstetrahydrocannabinol Milder drug similar to alcohol. At larger doses, changes in perception occurs sees lustrous colors and gets sharper hearing. May get extreme anxiety, depression, uneasiness, panic attacks etc. There is no tolerance, but could lead to psychological dependence.B.10.2 Discuss the structural similarities and differences between LSD, mescaline and psilocybin.LSD and psilocybin both have the Indole ring (Heterocyclic amine compound where the nitrogen atom is part of a ring).However, mescaline includes the benzene ring but not the indole ring it does have a primary amine.Serotonin also has the indole ring.B.10.3 Discuss the arguments for and against the legalization of cannabis.Cannabis offers relief from symptoms from AIDS, cancer and glaucoma. Marijuana may increase the appetite, and relieves nausea. Cannabis helps terminally ill patients to relieve tension and anxiety. Marijuana relieves pressure inside the eyeball for glaucoma patients.However there are many bad sides to it too. Smoking marijuana may lead to lung problems and may suppress the immune system. It might lead to rock-bottom fertility for men and cause brain damage and birth defects. Users may also start using harder drugs too.Users of prohibited drugs need to obtain it from bend sources and may therefore be forced into crime to support their habit. It damages the society a lot.