Applied Chemistry-Unit 1 and 4_2023-24_Part-1.pdf

APPLIED COMPONENT DRUGS  Definition Drug word derived from French word “Drogue” means herb According to WHO drug is defined as “ANY SUBSTANCE WHICH IS USED OR INTENDED TO BE USED FOR MODIFYING OR EXPLORING PHYSIOLOGICAL SYSTEMS OR PATHOLOGICAL STATES FOR THE BENEFIT OF...

APPLIED COMPONENT DRUGS  Definition Drug word derived from French word “Drogue” means herb According to WHO drug is defined as “ANY SUBSTANCE WHICH IS USED OR INTENDED TO BE USED FOR MODIFYING OR EXPLORING PHYSIOLOGICAL SYSTEMS OR PATHOLOGICAL STATES FOR THE BENEFIT OF THE RECIPIENT” Pharmacology is a branch of medicine and pharmaceutical sciences which is concerned with the study of drug or medication action, where a drug can be broadly or narrowly defined as any man-made, natural, or endogenous (from within the body) molecule which exerts a biochemical or physiological effect on the cell, tissue, organ, or organism. The two main areas of pharmacology are pharmacodynamics and pharmacokinetics Pharmacodynamic is a study of drug’s effect on body, so we can say it’s a studyof-what does DRUG do to the BODY. Pharmacokinetic-“What does BODY do to the DRUG” we have simple interchanged the BODY and DRUG to make a definition. And as per the definition our body responds to any drug by giving ADME effects.  An Ideal DRUGS Requirement of an Ideal drug: It should be localised at the site were it is desired to act. It should act on a system with efficiency and safety It should not have any toxicity and have minimum side effects It should not injure the host tissue or physiological processes The cell should not acquire tolerance or resistance to the drug after some time  Classification of DRUGS Classification of drug Two ways (a) Based on chemical type or according to structural units (b) Based on Therapeutic action (1) Functional or Pharmacodynamic agents (2) Chemotherapeutic agents (3) Vitamins (4) Hormones  Classification of drug Based on Therapeutic action (a) Functional or Pharmacodynamic agents Non-selective CNS depressants-hypnotics = natural sleep like and sedatives =non selective general depressants Selective Modifiers of CNS- Tranquilizers = treatment of mental disorders CNS stimulants-antidepressants =analgesic =insensibility to pain without loss of consciousness  Classification of drug Based on therapeutic action (a) functional or pharmacodynamic agents Adrenergic stimulant =increase the blood pressure and blocking agents Histamine =found in all organs and tissues=action on blood vessels = decrease the blood pressure by dilating capillaries and arteries and antihistaminic agents Local anaesthetics= absence of pain sensation=amino amide  Classification of drug Based on therapeutic action (a) functional or pharmacodynamic agents Cardio vascular agents= blood vessels and heart = distribution of blood Haematological agents= blood clotting=anticoagulants/ improve the hemeoglobin levels Diuretics= increase the out put of urine= kidney filters about180 litre of fluid each day  Chemotherapeutic agents Classification of drug CHEMOTHERAPEUTIC AGENTS THEY ACT IN SUCH AWAY THAT KILLS OR DESTROY THE DISEASE PRODUCING ORGANISM WITH OUT ANY HARM FULL EFFECTS ON THE CELLS IN WHICH ORGANISUM ARE PRESENT Classification of Chemotherapeutic agents  Organometallic compounds = at least one metal to carbon bond= cisplatin =anticancer  Anthelmintics = kill or eliminate parasitic worms  Antiprotozoals = some thing that destroys protozoa or inhibit their growth and ability of to reproduce  Antimalarials =protozoal disease=causes periodic fever= higher sickness Classification of Chemotherapeutic Agents Antifungal=used to treat fungal infections found on skin ,hairs and nails Antiviral= kills a virus suppresses its ability to replicate and hence inhibits Antiseptics=disinfectants germs and other microorganisms  Classification of chemotherapeutic agents Anti-Bacterials (sulpha drugs)=destroys bacteria and inhibit the growth, sulpha drugs are the first sulfonamide Anti-Bacterials (antibiotics)=kill the bacteria but not fight infections caused by viruses Anti-Tubercular and antileprosy drugs =due to mycobacteria = gram positive and acid-fast bacteria Anti-Neoplastics drugs =cancer or tumor =relative atonomous growth antibiotics  Nomenclature of DRUGS Chemical names or systematic names Generic official or common names (Non- Proprietory) Proprietory, trivial, brand or trade names  Nomenclature of DRUGS Chemical names or systematic names It should describe unambiguously the chemical structure of the drug According to rules of nomenclature of chemical compounds They are some times very elaborate and not suitable for routine usage  Example: Valium Chemical 7-chloro--1-methyl-5-phenyl-3H-1,4- benzodiazepin-2[1H]-one Generic Diazepam Trade Valium  Nomenclature of DRUGS Proprietory, trivial, brand or trade names It is individual name selected and used by manufactures It should be catchy, short easy to remember and name should suggest purpose for it is been used Brand names differ in different countries eg. Asprin is acetyl salicylic acid marketed with different trade names like Disprin, Analgin, Aspro, Anacin  Nomenclature of DRUGS Nomenclature of drug Synonyms Names given by different manufacturers Same drug have several names Diphenyl hydramine has 13 different names [2-Diphenylmethoxy-N,N-dimethylethylamine. Allerdryl. Benadryl, Benhydramin, Benylin, Benzhydramine Citrate, Diphenhydramine. Dimedrol]  Medicinal terms Definition of some medicinal terms Pharmacon = Drug Pharmacophore = The physiological activity of drugs have been found to depend on the presence of some particular functional groups or structural units, such part of drug causes the physiological effect is known as a pharmacophore  Medicinal terms By introducing pharmacophore compound can be made biologically active Its introduction to drug makes drug less toxic Examples: alkyl,hydroxy,alkoxy,aldehyde, ketone, halogen  Medicinal terms Prodrug a biologically active drug which by latentiation is converted into inactive carrier form is called prodrug Latentiation is a process of temporarily masking or concealing the activity of drug Prodrug on reacting with enzyme or non enzyme release the active drug Latentiation of drug produces Prolongation of action Shortening of action Drug localisation Transport regulation Adjuncts to pharmaceutical formulation Lessening of toxicity and side effects The Half-life efficiency of a drug is a pharmacokinetic parameter that is defined as the time it takes for the concentration of the drug in the plasma or the total amount in the body to be reduced by 50%. In other words, after one half-life, the concentration of the drug in the body will be half of the starting dose. Half life efficiency Information about the pharmacokinetics i.e. time course of drug absorption, elimination has an important role in understanding and planning of drug regimes Pharmacokinetics helps in the selection and adjustment of drug dose schedules Elimination of most of drugs occurs first order kinetics i.e. exponentially i.e. the constant fraction of the drug in the body disappears in each equal interval of time The rate of disappearance of drug from the body is reflected in the lowering of its plasma concentration Thus the drug removal from the body is proportional to its plasma concentration  Medicinal terms LD50 The median lethal dose Its the dose (mg/Kg) which would be expected to kill one half of an unlimited population of the same species and strain bacteria or test animal It also called as tolerance or threshold dose It is minimum dose cause the death of 50% test population LD50  Medicinal terms ED50 The median effective dose It the dose (mg/Kg) which produce a desired response in 50% of the test population It involves the treatment of group of patients with several doses in the increasing amount of standard preparation, then the minimum concentration required to have positive response for the 50% of test population is determined It is called as effective dose for 50% with standard  Medicinal terms Therapeutic index(TI) Therapeutic index(TI)= LD50/ED50 It is the approximate assessment of the drug and is expressed as ratio of the median lethal dose to the median effective dose Larger the value of therapeutic index safer is drug Depending upon the clinical use drug may have therapeutic index e.g. margin of safety of aspirin used for headache is greater than arthritic pain It gives rough idea about the safety of drug  Medicinal terms Receptor It is the portion of the molecule or structure with which the therapeutically active compound interacts producing series of events leading to an observable response Some structurally specific drugs after interacting with specific cellular components Chemically receptor is a chemical structure component Biologically receptor is micro-anatomical term  Medicinal terms Drug –receptor interaction The drug action is due to binding of drug to receptor site Drug binding due to ionic or non ionic forces Non ionic binding due to hydrogen bonding, hydrophobic bonding, van der waals forces. The interaction involves formation of drug receptor complex and the resultant response or effect  Medicinal terms Drug –receptor interaction K1 K3 D + R DR E K2 D = DRUG R =RECEPTOR DR = COMPLEX E = BIOLOGICAL EFFECT  Medicinal terms Drug potency Defined as maximum biological action which can be caused by minimum amount of drug administered A highly potent drug can cause high biological effect even minimum dose Potency also depends on the body weight and expressed as body weight per unit weight of drug to cause particular effect  Medicinal terms Drug potency Drug which is highly potent to children may not have much effect on adults Both of codeine and morphine are used as pain reliever Large dose of codeine cannot effectively relive severe pain which can be relive by smaller dose of morphine  Medicinal terms Drug potency If the concentration of the drug increases in the vicinity of the receptor than biological response would increase Initially higher concentration of drug rapidly increased the response but at this point most of receptors required to produce response have combined with drug If a drug is less potent but more selective it is one to be preferred Maximum efficacy is the one of the primary determinants of choice of a drug “Potency denotes the amount of drug needed to produce a given effect” “Efficacy: Refers to the relative ability of a drug-receptor complex to produce a maximum functional response”  Medicinal terms Bioavailability It is defined as the percentage of the biologically active drug which is absorbed from a given dosage from and reaches the systemic circulation in the in the body following administration of the drug When drug is given by intravascular route the bioavailability is 100% Much less in case of oral administration  Medicinal terms Bioavailability When the drug is given by oral route the drug may not be fully absorbed or it may undergo metabolic changes in liver or intestines or may be extracted before it is absorbed The bioavailability can be found by measuring the concentration of drug in blood and urine sample at regular intervals and plotting the concentration-time curve  Medicinal terms Bioavailability varies with following factors Properties of drug like particle size, solubility, hydrated state, the metal salt used, chiral characteristic Water soluble drug are have higher bioavailability as they are easily absorbed Racemic mixture ,Chiral molecules may give less than 50% since only one optical isomer is biologically active  Medicinal terms Drug toxicity Drug administration is always followed by the expected reactions considered to be toxic reactions This may cause mild skin rash to major blood pressure abnormality, liver damage It may be acute (short term) toxicity It may be chronic (long term) toxicity  Medicinal terms Drug addiction The body cell readjusts to the absence of drug unnoticeably After the drug withdrawal a psychic craving for the drug is observed which leads to physical disturbances This syndrome is called as addiction Observed for morphine -cocaine  Medicinal terms Spurious drugs Drug shall be deemed to be spurious…. if it is imported under a name which belong to another If it is imitation or substitute for another If label or container bears name of company which does not exist If it has been substituted wholly or parts by another drug or substance If it purports to be product of manufacturer of whom it is not truly a product  Medicinal terms Misbranded drug A drug shall be deemed to be misbranded If it is so coloured , powdered or polished that damage is concealed If it is made to appear of better or greater therapeutic value than it really is It is not labelled in the prescribed manner If its label or container makes false claim or misleading in any manner  Medicinal terms Adulterated drugs The drug shall be deemed to be adulterated If it consist of in whole or in parts any filthy, putrid or decomposed substance If it has been prepared, packed or stored under unsanitary conditions whereby it may be contaminated Or whereby it may have been render the contents injurious to health If its contains any harmful or toxic substance which may be injurious to health If it bears or it contains, for the purposes of colouring only a colour other than one which is approved If the drug has been mixed with any other substance so as to reduce its quality or strength  Medicinal terms Pharmacopoeia Pharmakon= a drug and poiein= to make Is a book of directions and requirement for the preparation of medicine It is generally published by authority Pharmacopoeia is a legislation of the country which sets standards and obligatory quality indices for the drug, raw materials used to prepare them  Medicinal terms Pharmacopoeia These regulations are present separately , in general and specific for articles Only the pharmaceuticals which are commonly and currently in used are included in the pharmacopoeia  Medicinal terms Pharmacopoeia the substances which are found to be undesirable from the past experience and which are currently not in use are exclude Only minimum standard for the chemicals are prescribed  Medicinal terms British pharmacopoeia(B.P.) It was pioneer in this field First edition in 1833 Most standard pharmacopoeia The medication not as per the standards are withdrawn  Medicinal terms Indian pharmacopoeia(I.P.) Published in 1985 Third edition 1989 Central indian pharmacopoeia laboratory at gaziabad  Medicinal terms United states pharmacopoeia(U. S.P.) First got release on 1850 It covers all pharmaceutical chemicals , raw materials, formulation cosmetics, vitamins, hormones U S generally does not allowed to import medicines and food products unless they are made as per USP