L-1 Introduction to Pharmacology & Drug History PDF - GMU

L-1 Introduction to Pharmacology and the History of Drugs Dr. Salma Naqvi Asst. Prof., Pharmacology GMU May 23, 2022 www.gmu.ac.ae...

L-1 Introduction to Pharmacology and the History of Drugs Dr. Salma Naqvi Asst. Prof., Pharmacology GMU May 23, 2022 www.gmu.ac.ae COLLEGE OF ALLIED HEALTH SEIENCES  Learning objectives Define the terms “Pharmacology”, ‘drug” List the major divisions of pharmacology List the various sources of drugs with examples. Define proprietary, non-proprietary and chemical names Define schedule drugs and describe the five categories of controlled substances. Describe the various routes of administration of drugs  Pharmacology Pharmacon –drug; logos - science Study of effects of drugs on living system Science which deals with the mechanism of action, therapeutic uses, adverse effects and fate of drugs in human beings or animals  Drug A drug or a medicine is a nonfood chemical substance which affects the mind or the body Chemical substance used for the treatment, cure, prevention or diagnosis of a disease in humans / animals  Drug categories Non- prescription drugs / OTC: safe drugs and can be sold over the counter by the chemist without prescription (vitamins, antacids, paracetamol etc) Prescription drugs: classified in various Schedules and Drug Acts, used under medical supervision, dispensed by an order of a registered medical practitioner (RMP) (antibiotics, antihypertensives etc)  Drug nomenclature Every drug has 3 types of names Chemical name: Describes chemical constitution of a drug Aspirin: acetyl salicylic acid Paracetamol: p-acetamido phenol Proprietary name / brand name Name assigned by the manufacturer for advertising Aspirin: Disprin, Ecosprin Paracetamol: Panadol, Crocin  Drug nomenclature contd.. Non proprietary name / Generic name Name assigned by scientific body (USAN), only when the drug has been found to be useful Used uniformly all over the world e.g., Aspirin, Paracetamol USAN: United States Adopted Names  Pharmacology: Division PHARMACOLOGY PHARMACOKINETICS PHARMACODYNAMICS  Pharmacokinetics Pharmacodynamics What body does to drug: What drug does to body: How drugs move The mechanism of action through the body in the by which drugs produce processes of absorption, their effects (desired or distribution, metabolism, undesired) based on time and excretion and dosage Pharmacokinetics  Molecular pharmacology The study of the chemical structures of drugs and the action of drugs at the molecular level within cells. Pharmacogenetics How the genetic makeup of different people affects their responses to certain drugs Pharmacogenomics Using genome technology to discover new drugs. Pharmacotherapy Using drugs to affect the body therapeutically  Sources of drugs Animals: Insulin, Heparin, Vitamin B12 Plant: Morphine (Opium), Digoxin, atropine, oils, gums, tannins etc Minerals: ferrous sulfate, sodium bicarbonate, Magnesium sulfate Microbiological: Penicillin from fungi Synthetic: Analgesics, Antimicrobials Genetic engineering (rDNA): Insulin  Schedule drugs Drugs and other substances that are considered controlled substances under the Controlled Substances Act (CSA) of USA, according to their potential of abuse Divided into 5 schedules Schedule I Extremely high potential for abuse and addiction No currently accepted medical use Not available under any circumstances, even with a prescription Schedule II High potential for abuse and addiction Currently accepted medical uses Requires an official prescription form Severe physical and psychological dependence may result Schedule III Less potential for abuse and addiction than Schedule II drugs Currently accepted medical uses Moderate physical and psychological dependence may result. Schedule IV Less potential for abuse and addiction than Schedule III drugs Currently accepted medical uses Limited-to-moderate physical or psychological dependence may result Schedule V Limited potential for abuse Currently accepted medical uses Controlled substance symbol The capital C stands for controlled substance. The No. written inside (always a roman numeral) indicates the assigned schedule. It is important to remember that a C with the roman numeral IV inside it does noit mean that the drug is to be given by iv route. It means that the drug is a Schedule IV controlled substance History of Drugs Drugs in Ancient Times: Pharmacology is one of the oldest branches of medicine as early as 2000 B.C. The Egyptians treated diseases with substances such as frogs’ bile, sour milk, lizards’ blood, pigs’ teeth, sugar cakes, dirt, spiders’ webs, hippopotamus’ oil, and toads’ eyelids. The Egyptians applied moldy bread to abrasions, a practice that actually had some therapeutic basis as, many centuries later, penicillin was extracted from a mold. An Egyptian medicinal scroll, the Ebers Papyrus from 1500 B.C. (discovered in the early 1800s), contained the names of 800 different herbal formulations and prescriptions. History contd.. The ancient Chinese practiced healing arts that emphasized the use of herbs and some minerals, but few animal products. Herbal preparations were used in conjunction with acupuncture, massage, and exercise. The Greeks and Romans furthered the study of medicine through an understanding of anatomy and physiology, which was an important first step toward understanding how drugs exert their effects in the body. In the 1600s, patients were advised to eat soap to cure blood in the urine and put mercury in beer to cure intestinal worms. Modern Drugs Derived from Natural Sources Drugs Derived from Plants: e.g. foxglove plant: A derivative of this plant is used to make the drug digoxin (Lanoxin), which is still used today to treat congestive heart failure. Drugs Derived from Animals: Thyroid supplement drugs are composed of dried (desiccated) thyroid gland tissue taken from animals. Thyroid supplement drugs are used to treat patients with hypothyroidism. Drugs Derived from Minerals: Minerals, such as calcium and iron, are available as individual dietary supplements, and trace minerals, such as copper, magnesium, selenium, and zinc, are included in many multivitamin supplements.  History Cocaine in a common drug. This 1885 advertisement was for the drug Cocaine Toothache Drops. It was not known at that time that cocaine was a highly addictive drug. Children as well as adults became addicted to this drug.  Drug Legislation and Drug Agencies Federal government Protect consumers Regulate the industry State government Practice acts Dispensing and administration  Federal and state roles Federal Food and Drug Act Passed in 1906 Standards for Quality Proper Labeling of medications Federal Food, Drug, Cosmetic Act — 1938 Drug effectiveness Animal testing of the drugs FDA Approval required by pharmaceutical companies to bring their products to the market. Approval was contingent based on effect of drugs on animals.  Federal and state roles Food, Drug, Cosmetic Act 1938 Established FDA Warning labels Durham-Humphrey amendments to Food, Drug, Cosmetic Act were passed in 1952. These required: Physician’s order to dispense Prescription drugs Established Over-the-counter (OTC) category of drugs, that do not require prescription.