Week 2 - Introduction to Pharmacology.pdf

Introduction to Pharmacology Dr. Ian Christopher N. Rocha NU College of Allied Health PHARMACOLOGY AND THERAPEUTICS Etymologically, it is the science of drugs (Greek pharmakos, medicine or drug; and logos, study). In actual use, however, its meaning is limited to the study of the action...

Introduction to Pharmacology Dr. Ian Christopher N. Rocha NU College of Allied Health PHARMACOLOGY AND THERAPEUTICS Etymologically, it is the science of drugs (Greek pharmakos, medicine or drug; and logos, study). In actual use, however, its meaning is limited to the study of the actions of drugs. It has been defined as “an experimental science which has for its purpose the study of changes brought about in living organisms by chemically acting substances (with the exception of foods), whether used for therapeutic purposes or not.” It is a branch of medicine that deals with the interaction of drugs with the systems and processes of living animals, in particular, the mechanisms of drug action as well as the therapeutic and other uses of the drug. DRUGS – any substance that brings about a change in biologic function through its chemical actions SOURCES OF DRUGS CLASSIFICATION OF THERAPEUTIC AGENTS This type of categorization of drugs is from a medical perspective and categorizes them by the pathology they are used to treat. Drug classes that are defined by their therapeutic use include: Analgesics Antipsychotic Antibiotic Antispasmodic Anticancer Antiviral Anticoagulant Cardiovascular Antidepressant Depressant Antidiabetic Sedative Antiepileptic Stimulant PRESCRIPTION DRUGS Prescribed by a licensed physician Bought at a pharmacy Prescribed for and intended to be used by one person Regulated by the Food and Drug Administration OVER-THE-COUNTER (OTC) DRUGS Drugs that do NOT require doctor’s prescription Bought off-the-shells in stores and pharmacies Regulated by Food and Drug Administration DRUG REGULATIONS AND STANDARDS The regulation of food and drugs in the Republic of the Philippines is enshrined in the 1987 Philippine Constitution Statutory laws are also in place providing legal basis for the creation of a regulatory agency, FDA, mandated to ensure the safety, efficacy and good quality of all food and drug products being made available to the general public The most important of these laws are RA 3720 (Foods, Drugs, Medical Devices and Cosmetics Act), RA 6675 (Generics Act), RA 8203 (Act Prohibiting Counterfeit Drugs), and RA 7394 (Consumers Act) Regulation is achieved through inspection and licensing of food and drug establishments, registration and market monitoring of products, approval of product label prior to marketing, and approval and monitoring of promotions and advertisements. DRUG REGULATIONS AND STANDARDS International standards and guidelines such as those recommended by the WHO, USP or BP, FAO and Codex Alimentarius are used as a basis in the formulation and implementation of rules and regulations governing the manufacture, importation, exportation, distribution, or sale of food and drugs. Compliance with the requirements of good manufacturing practice is the basis criterion for licensing food and drug establishments, while safety, efficacy and good quality are the criteria for registration of products. Although cigarettes are not regarded as food or drug, the labeling and promotion of such is being regulated by the Bureau because of the hazard posed to public health. EVALUATION OF DRUGS 1. Pre-clinical Tests – involve non-human subjects such as animals 2. Clinical Trials – involve human subjects ANIMAL STUDIES ANIMAL STUDIES ANIMAL STUDIES ANIMAL STUDIES ANIMAL STUDIES CLINICAL TRIALS CLINICAL TRIALS CLINICAL TRIALS CLINICAL TRIALS CONTROLLED SUBSTANCES CONTROLLED SUBSTANCES DRUG SCHEDULE DRUG SCHEDULE DRUG SCHEDULE ORPHAN DRUGS a medication or other medicinal product used to treat a rare disease or disorder called an “orphan drug” because due to its limited market, unlikely to be adopted by a pharmaceutical company GENERIC DRUGS vs BRANDED DRUGS DRUG DOSAGE PREPARATION Solid, semi-solid, liquid, and gaseous  SOLID DRUG PREPARATION Powders: solid dosage forms containing finely divided particles in micron size Tablets: solid dosage form containing medicaments with or without excipients Granules: aggregate of particles Capsules: drug enclosed with gelatin capsule Cachets: drugs enclosed with wafer sheet of rice Pills: small tablet containing excipients Lozenges: solid preparations containing sugar and gum used to medicate mouth and throat Suppositories: solid dosage containing medicaments with suitable suppository base that inserted in to the body cavities other than mouth, like rectum, nose, ear Poultices: solid dosage form converted to paste like preparation used externally in the skin to reduce inflammation  SEMI-SOLID DRUG PREPARATION Ointments: semi-solid dosage forms for external use containing with or without medicaments with suitable ointment base Creams: semi-solid dosage forms for external use containing with or without medicaments with suitable fatty base Paste: semi-solid dosage forms for external use containing high proportion of finely powdered medicaments with suitable fatty base Gels: transparent semi-solid dosage forms for external use containing hydrophilic or hydrophobic base with gelling agents Poultices: semi-solid dosage forms for external use containing medicaments applied to the skin to hold the dressing and protective  LIQUID DRUG PREPARATION Collodions: liquid preparations for external use having nitro cellulose used to protect the skin Droughts: liquid preparations for oral containing medicaments available in single dose or multiple dose Elixirs: liquid preparation for oral containing medicaments with suitable excipients Emulsions: biphasic liquid dosage form for oral containing medicaments in which fine oil globules dispersed in continuous phase Suspensions: biphasic liquid dosage form for oral containing medicaments in which fine solid particles suspended in continuous phase Enemas: liquid preparation for rectal containing medicaments Gargles: concentrated aqueous solutions for external use used to treat throat infections Gels: aqueous colloidal suspensions containing medicaments used as antacids Linctus: viscous, liquid oral preparations used to relief cough Lotions: liquid preparations for external application usually applied without friction  LIQUID DRUG PREPARATION Liniments: liquid preparations for external application usually applied with friction Mixtures: liquid oral preparations containing one or more medicaments Mouth washes: concentrated aqueous solutions for external use used to treat mouth infections and oral hygienic Nasal drops: liquid preparations containing medicaments that are instilled in to the nose with a dropper used to treat nose infections and blockage of nose Paints: liquid preparations for external application to the skin or mucous membrane with soft brush Solutions: clear liquid preparation containing with or without medicaments used to internal or external preparations Syrups: sweet, viscous, concentrated liquid preparations containing with or without sugar and medicaments  GASEOUS DRUG PREPARATION Aerosols: suspension of fine solid or liquid particles with gas used to apply drug to respiratory tract having atomizer with in device Inhalations: internal liquid preparations containing medicaments dissolved in suitable solvent or if insoluble suspended in the propellent Sprays: gaseous preparations of drugs containing alcohol applied to mucous membrane of nose or throat with atomizer or nebulizer DRUG ADMINISTRATION