Introduction to general Pharmacology

Introduction to Pharmacology- Definition, historical landmarks and scope of
pharmacology, nature and source of drugs, essential drugs concept and routes of
drug administration

1. UNIT-1:General pharmacology Part : 1 Introduction to Pharmacology Ms. Kanchan chouksey Pharmacy, Medi -caps University, Indore Email :

2. BP 404 T Pharmacology I Ms. Kanchan chouksey Unit I a. Introduction to Pharmacology b. Pharmacokinetics Unit II a. Pharmacodynamics, b. Adverse drug reaction, c. Drug Interactions d. Drug discovery and clinical evaluation of new drugs Unit III Pharmacology of drugs acting on Peripheral nervous system Unit IV Pharmacology of Drugs acting on Central Nervous system Unit V Pharmacology of Drugs acting on Central nervous system

3. Books Text Books K.D. Tripathi A Text book of Pharmacology Sparsh gupta A textbook of Pharmacology Reference Books Goodman and Gilman’s A Text book of Pharmacology Rang H.P., Dale M.M., A Text book of Pharmacology Lippincott A Textbook of Pharmacology Other Books Sharma H.L. , Sharma K.K., A textbook of Pharmacology, and many others Ms. Kanchan chouksey

4. Pharmacology : Pharmacology is all about study of - 1.Drug 2.Drug effect 3.Body response to drug Ms. Kanchan chouksey

5. The word pharmacology comes from the Greek words  : Pharmacon means : Drug / Medicine Logos means : To study Ms. Kanchan chouksey

6. Continue: Pharmacology is the study of drugs including their origins, history, uses, and properties. It mainly focuses on the actions of drugs on the body. Ms. Kanchan chouksey

7. Definition : In a broad sense, it deals with interaction of exogenously administered chemical molecules with living systems, and any single chemical substance which can produce a biological response is a ' drug'. Ms. Kanchan chouksey

8. Drug: It is the single active chemical entity present in a medicine that is used for diagnosis, prevention , treatment/cure of a disease . Ms. Kanchan chouksey

9. Clinically drugs used for: Diagnosis : Barium salts (Barium sulphate ) Prevention : Vaccines/ chemoprophylaxis Treatment : Antibiotics, Disease, disorder Alteration of physiological processes: Hormones & their derivatives (insulin, GH, contraceptive) Global effect: General anesthetics Ms. Kanchan chouksey

10. Some terms related to Pharmacology: Drug – Drugs are substance which can change the physical and physiological state Medicine - Medicine are the drug which are used to treat illness or discomfort Dose - Certain amount of drug Dosage Form - It is the Physical form of medicine Ms. Kanchan chouksey

11. Continue… Onset of drug action : The time between drug administration and beginning of therapeutic effect Duration of action : Time of drug to produce therapeutic effect Intensity of drug action : It is a maximum pharmacological response produce by the peak concentration of drug Peak concentration ( Cmax ) : The point at which maximum concentration of drug reached in plasma Ms. Kanchan chouksey

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13. The two main divisions of pharmacology are Pharmacodynamics and Pharmacokinetics Ms. Kanchan chouksey

14. 1.Pharmacodynamics (Greek: dynamis -power ) What Drug Does With The Body : This includes physiological and biochemical effects of drugs and their mechanism of action at organ system/subcellular/macromolecular levels E.g .- Adrenaline interaction with adrenoceptors G-protein mediated stimulation of cell membrane bound adenylyl cyclase Increased intracellular cyclic AMP cardiac stimulation, hyperglycaemia Ms. Kanchan chouksey

15. Adrenaline interaction with adrenoceptors : Ms. Kanchan chouksey

16. Adrenaline interaction with A drenoceptors : Ms. Kanchan chouksey

17. This refers to movement of the drug in and alteration of the drug by the body It includes absorption, distribution, binding/localization/storage , biotransformation and excretion of the drug Ms. Kanchan chouksey 2.Pharmacokinetics (Greek: Kinesis-movement)- What The Body Does To The Drug

18. What The Body Does To The Drug: Ms. Kanchan chouksey

19. History of Pharmacology: Knowledge of drugs and their uses in diseases are as old as history of mankind Primitive men gather the knowledge of healing and medicines by observing the nature , noticing the animals while ill and personal experience after consuming plants and herbs as remedies. They extracts from plants, animals and minerals had medicinal effects on body tissue. These discoveries became the foundation of pharmacology. Ms. Kanchan chouksey

20. Historical development in Pharmacology: Hippocrates (460-375 BC) – A greek physician consider “father of medicine” He was the first person recognize disease as abnormal reaction of body He introduced use of metallic salts for the treatment of disease Theophrastus (380-287 BC) – He called as “father of Pharmacognosy ” He classified medicinal plants on the base of medicinal characteristics Ms. Kanchan chouksey

21. Continue… Dioscorides ( AD 57) – He produced one of the first materia medica of approximately 500 plants and remedies Valerius cordus (1514-1544)- He compiled the first pharmacopeia where he described techniques for the preparation of drugs. Ms. Kanchan chouksey

22. Modern Pharmacology- Conversion of old medicines into the modern pharmacology start taking shape following the introduction of animal experimentation and isolation of active ingredients from plants Ms. Kanchan chouksey

23. Landmarks of Modern Pharmacology: Francois Megendie ( 1783- 1855) - He was the first pharmacologist established the foundation of modern pharmacology. He developed experiment to elucidate the physiological processes and action of drugs on the body. Frederich serturner - He was the G erman pharmacist’s assistant , isolated morphine – the first pure drug in 1805 Ms. Kanchan chouksey

24. Continue…. Ostwald schmiedeberg (1838-1921 )- “ father of Pharmacology” established pharmacology as an independent discipline. In 1872 set up an institute of pharmacology in Strasbourg, France (Germany at that time) which became a mecca for students who were interest in pharmacological problems. Ms. Kanchan chouksey

25. Basic areas of Pharmacology: Ms. Kanchan chouksey Pharmacokinetics: deals with absorption, distribution, biotransformation & excretion of drugs . Pharmacodynamics : study of biochemical & physiological effects of drugs & their Mechanism of action . Pharmacotherapeutics : use of drugs in prevention & treatment of disease .

26. Continue…. Chemotherapy : effect of drugs upon microorganisms, and neoplastic cells living & multiplying in living organism . Toxicology: branch of pharmacology which deals with the undesirable effects of chemicals on living systems . Ms. Kanchan chouksey

27. NATURE & SOURCES OF DRUGS: Natural drugs- Plants : Many plants contain biologically active substances and are the oldest source of drugs. e.g . use of opium, belladonna, ephedra. cinchona. curare, foxglove, sarpagandha , Ms. Kanchan chouksey

28. Chemically the active ingredients of plants fall in several categories: Ms. Kanchan chouksey Alkaloids: These are alkaline nitrogenous bases having potent activity, and are the most important category of vegetable origin drugs. Prominent examples are: morphine, atropine, ephedrine, nicotine, ergotamine, reserpine, quinine, vincristine,

29. Continue… . Ms. Kanchan chouksey b . Glycosides: Glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Cardiac glycosides (Digoxin, Digitoxin ) are the best known glycosidic drugs. Aminoglycosides (gentamicin) are antibiotics obtained from microorganisms

30. Continue…. 2. Animals Exploration of activity of organ extracts in the late 19th and early 20th century that led to introduction of animal products into medicine E.g. adrenaline, thyroxine , insulin, liver extract ( vit . B 12). Antisera and few vaccines are also produced from animals Ms. Kanchan chouksey

31. Continue… , . Ms. Kanchan chouksey 4. Synthetic drugs: Prepared by chemical synthesis in pharmaceutical laboratories. E.g. Sulphonamides, quinolones ,barbiturates. 3. Microbes Antibiotics are obtained from fungi, actinomycetes and bacteria, E.g. penicillin, gentamicin, tetracycline, crythromycin , polymyxin B. Some enzymes- E.g. diastase from a fungus and streptokinase from streptococci have a microbial source. Vaccines are produced by the use of microbes 5. Biosynthetic drugs: Prepared by cloning of human DNA in to the bacteria like E.coli . E.g. Human insulin ( humulin ), human GH .

32. ESSENTIAL MEDICINES (DRUGS) CONCEPT: Ms. Kanchan chouksey The WHO has defined essential Medicines (drugs) as " those that satisfy the priority healthcare needs of the population.” They are selected on the basis of – Public health relevance- disease in country Evidence on safety and efficacy Comparative cost effective

33. Continue… WHO brought out its first Model List of Essential Drugs along with their dosage forms and strengths in 1977 . This has been revised from time to time and the current is the 20th list (2017 ) which has 433 medicines. India produced its National Essential Drugs List in 1996, and has revised it in 2011, and now in 20 15 with the title "National List of Essential Medicines ". Ms. Kanchan chouksey

34. Essential Medicines 18th edition (1977)- WHO Model List  Examples of some essential medicine 1.Antibacterials: azithromycin, ciprofloxacin 2. Inhalational medicines - halothane , isoflurane   ( General anesthetics ) 3 . Injectable medicines : ketamine, propofol ( General anesthetics ) 4. Medicines For Pain: acetylsalicylic acid, ibuprofen, paracetamol 5. Antituberculosis medicines : ethambutol , isoniazid, pyrazinamide, rifampicin Ms. Kanchan chouksey

35. Drug Nomenclature A drug has at least three types of names: 1. Chemical name (IUPAC) or scientific name- Based on molecular structure of the drug. E.g. 2-acetoxybenzoic acid/ acetyl salicylic acid 2. G eneric name- Given by FDA/WHO while approved, the short hand version of chemical name. Recommended in RX . E.g. Aspirin 3. Brand name- It is the name assigned by the manufacturer(s) and is his property or trade mark . One drug may have multiple proprietary names, E.g . Jusprin ®, disprin Ms. Kanchan chouksey

36. Routes of Drug administration Is the path by which a drug , fluid, poison or other substance is brought into contact with the body Ms. Kanchan chouksey

37. Commonly Used Routes of Drug Administration Ms. Kanchan chouksey

38. ROUTES OF DRUG ADMINISTRATION Most drugs can be administered by a variety of routes. The choice of appropriate route in a given situation depends both on drug as well as patient related factors. Routes can be broadly divided into those for - ( a) Local action ( b) Systemic action Ms. Kanchan chouksey

39. LOCAL ROUTES These routes can only be used for localized organs/ tissue at approachable sites and for drugs whose systemic absorption from these sites is minimal or absent. Thus , high concentrations are attained at the desired site without exposing the rest of the body. Systemic side effects or toxicity are consequently absent or minimal. E.g . glyceryl trinitrate (GTN) applied on the skin as ointment or transdermal patch for angina pectoris ( chest pain) Ms. Kanchan chouksey

40. The local routes are : 1. Topical This refers to external application of the drug to the surface for localized action. It is often more convenient as well as reassuring to the patient. Drugs can be efficiently delivered to the localized lesions on skin, nasal mucosa, eyes, ear canal, anal canal or vagina in the form of lotion, ointment, cream, powder, rinse, drops , spray, suppositories or pesseries . Ms. Kanchan chouksey

41. Continue… 2 . Deeper tissues Certain deep areas can be approached by using a syringe and needle, but the drug should be in such a form that systemic absorption is slow . e.g . intra-articular injection (hydrocortisone acetate in knee joint ), intrathecal injection ( lidocaine ) 3. Arterial supply Close intra-arterial injection is used for contrast media in angiography. Example: gadolinium contraxt used for MRI , Iodinated contraxt used for CT scan , angiography Ms. Kanchan chouksey

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43. SYSTEMIC ROUTES Systemic administration is a route of administration of medication, nutrition or other substance into the circulatory system so that the entire body is affected. Administration can take place via enteral administration or parenteral administration.  Systemic Routes include oral, sublingual, transdermal, nasal, inhalational, rectal and other parenteral routes (intravenous, intramuscular, intradermal and subcutaneous ) Ms. Kanchan chouksey

44. Enteral Route: Ms. Kanchan chouksey Oral route is safer and economical but several drugs are not effective by this route because of high first pass metabolism in the liver and intestinal wall (e.g. nitrates, lignocaine, propanolol , pethidine ).

45. Continue… Advantages: - Convenient - portable, safe, no pain, can be self-administered. Cheap - no need to sterilize (but must be hygienic of course) Variety of dosage forms available - fast release tablets, capsules, enteric coated, layered tablets, slow release, suspensions, mixtures Convenient for repeated and prolonged use. Ms. Kanchan chouksey

46. Continue… Disadvantages : - 1.Sometimes inefficient :- high dose or low solubility drugs may suffer poor availability, only part of the dose may be absorbed. First-pass effect :- Drugs absorbed orally are transported to the general circulation via the liver. Thus drugs which are extensively metabolized will be metabolized in the liver during absorption . e.g. the propranolol oral dose is somewhat higher than the IV, the same is true for morphine Ms. Kanchan chouksey

47. Continue.. 2. Food :- Food and G-I motility can effect drug absorption. Often patient instructions include a direction to take with food or take on an empty stomach . Absorption is slower with food for tetracyclines and penicillins , etc 3. Unconscious patient :- Patient must be able to swallow solid dosage forms. Liquids may be given by tube Ms. Kanchan chouksey

48. 1. Sublingual route Avoids first pass metabolism, can be used in emergencies, can be self administered and also after getting the desired action, rest of the drug can be spitted. Drugs like nitroglycerine (AP), isosorbide dinitrate (AP), clonidine (HBP) etc. can be administered by sublingual route. Ms. Kanchan chouksey

49. Continue… ADVANTAGES Economical Quick termination First-pass avoided Drug absorption is quick Can be self administered DISADVANTAGES Unpalatable & bitter drugs Irritation of oral mucosa Large quantities not given Few drugs are absorbed Ms. Kanchan chouksey

50. 2 . Rectal route Certain irritant and unpleasant drugs can be put into rectum as suppositories or retention enema for systemic effect . Example : enema used for childrens for bowel movement ADVANTAGES DISADVANTAGES Used in children Inconvenient Little or no first pass effect Absorption is slow and erratic Used in vomiting/ unconsciuos Irritation or inflammation of rectum mucosa Ms. Kanchan chouksey

51. Continue… 3 . Inhalational route : Inhalation Volatile liquids and gases are given by inhalation for systemic action, e.g. general anaesthetics – Nitric oxide, Halothane. The drugs administered by this route include drugs for asthma (e.g ., salbutamol) Ms. Kanchan chouksey

52. Ms. Kanchan chouksey 4. IV, IM ,SUBCUTENOUS

53. Parentral : Conventionally, parenteral refers to administration by injection which takes the drug directly into the tissue fluid or blood without having to cross the enteral mucosa. Ms. Kanchan chouksey

54. Time of onset Intravenous 30-60 seconds Intraosseous 30-60 seconds Endotracheal 2-3 minutes Inhalation 2-3 minutes Sublingual 3-5 minutes Intramuscular 10-20 minutes Subcutaneous 15-30 minutes Rectal 5-30 minutes Ingestion 30-90 minutes Transdermal (topical) variable (minutes to hours) Ms. Kanchan chouksey

55. Questions Ms. Kanchan chouksey Ms. Kanchan chouksey

56. Thank You Great God, Medi-Caps, All the attendees Ms. Kanchan chouksey Ms. Kanchan chouksey