Pharmacy Orientation - Second Lecture (King Salman University)

Field of Pharmacy Sciences Bachelor of Pharmacy-PharmD (Clinical Pharmacy Program) Pharmacy Orientation & Medical Terminology (PPH101) Lecture 2 Date: 15 /10 /2024 Dr: Ramy Elsergany, PhD Department of Pharmaceutics & Industrial Pharmacy ...

Field of Pharmacy Sciences Bachelor of Pharmacy-PharmD (Clinical Pharmacy Program) Pharmacy Orientation & Medical Terminology (PPH101) Lecture 2 Date: 15 /10 /2024 Dr: Ramy Elsergany, PhD Department of Pharmaceutics & Industrial Pharmacy  Drug Sources Drugs have many sources: 1. Plants 2. Animals 3. Minerals 4. Synthetic 5. Semisynthetic 6.Bacteria (Prepared by biotechnology) 2  Medicinal Plants Plants were the major source of oldest drugs. Extracts of plants may be used 1. Without further processing (crude drugs) 2. With technical processing (prepared drugs) The drugs can be obtained from leaf, seed, fruit, flower, stem and root 3  Plant based drug oDigoxin is obtained from Digitalis Lanata leaf, used for treatment of congestive heart failure. oAtropine from Belladona used as antispasmodic oTannin from Coffee seeds used as astringent. oEugenol oil from clove used as a local anesthetic for toothache. 4 Animal based drug ✓Drugs from animal sources are lesser in number. Examples: 1. Heparin obtained from Mexican medical leech (whole animal) 2. Insulin from bovine pancreas 3. Cod liver oil from Gadus spp. 4. Vitamine B12 extracts from liver 5. Vaccines 5  Minerals ❑Minerals have been used as drugs since ancient times. ❑Both metallic and non-metallic minerals are commonly used as drugs. Examples: Metallic: 1. Ferrous sulphate as haematinic. 2. Magnesium sulphate as purgative 3. Aluminium hydroxide as antacid Non-Metallic: 1. Hydrogen peroxide as antiseptic 2. Radio-isotopes of iodine as diagnostic and therapeutic agents in thyroid disorders. 6  Synthetic drugs oThose are totally prepared in the laboratory. oOne of the earliest synthetic drugs was sulphonamide, aspirin and paracetamol. Advantages of synthetic drugs over natural or semi-synthetic drugs: oChemical purity oHigh quality, which can be manually controlled oImproved safety profile, particularly in terms of antigenicity oCost-effective preparation methodology 7  Semisynthetic drugs ✓ Drugs are originally natural compounds but with a little modification of their chemical structures. ✓The basic nucleus is kept the same as the natural source while altering the chemical structure. Examples: 1. Heroin (semisynthetic drug) from morphine (natural drug) Penicillin 2. Ampicillin (semisynthetic) from penicillin (bacterial source) Advantage of Ampicillin over Penicillin: ✓The presence of amino group (NH2) in ampicillin structure leads to hydrolysis resistance to stomach acid, and thus used orally in contrast to penicillin used by IV route only. Ampicillin 8  Microbiota as Drug Sources Antibiotics are historically derived from micro-organisms. Examples 1.Penicillin from penicillum notatum 2.Bacitracin from Bacillus Subtilis 3.Insulin can be produced by using E.Coli as a factory for its production (biotechnology through gene extraction) 9 Naming of drugs ✓ Every drug has three names 1. Chemical Name This name is given when a new chemical entity (NCE) is developed. It is a scientific name based on the chemical structure of the drug. It is also known as IUPAC (International Union of Pure and Applied Chemistry) name. Example: 2- Acetoxybenzoic acid (Aspirin) 10  Naming of drugs 2. Generic name oIt is also known as the International Nonproprietary Name (INN) given to the drug during early investigation. oIt is assigned by an official body, the United States Adopted Names (USAN) Council. oAlso, it is known as official name of drug which is registered later in pharmacopeia oThe generic name of Aspirin is acetyl salicylic acid 11  Naming of drugs 3. Brand name (trade name) ❑ It is developed by the company requesting approval for the drug name. ❑Brand name is developed as generic name is hard to remember. ❑Brand name and generic name have to be approved by regulatory body such as FDA. ❑Both names are given after ensuring that drugs are safe and effective. ❑Generic and brand names of each drug developed must be unique to prevent one drug being mistaken for another when drugs are prescribed and dispensed. ❑Every drug has one generic name but many brand names. ❑Acetylsalicylic acid (generic name) is present in different brand names such as Aspirin®, Aspocid®, Juspirin®, Aggrex® and Aspirin®protect 100. 12 Naming of drugs ✓Sometimes, the brand name of a specific pharmaceutical company of the same API has different brand names due to cultural considerations. ✓For example, Arava® developed by Sanofi Aventis, France was not accepted to possess the same name in Egypt, So, Egyptian Drug Authority decided to change from Arava® to Avara®. 13 Naming of drug Chemical name: 4- or para (acetylamino) phenol Official name: paracetamol (BP) or acetaminophen (USP) Brand names: Tylenol®, Abimol®, Cetal®, Paramol® and Adol® 14  Types of dosage forms Dosage form: The physical appearance of the medicine and the way the medicine releases the drug and delivers it to the body or more specifically to the target organ. Dosage forms are classified according to their physical state: 1. Gaseous such as inhalation anesthetics and aerosols. 2. Liquid such as solutions, emulsions and suspensions. 3. Solids such as effervescent powders, granules, tablets and capsules. 4. Semisolids such as creams, ointments, gels and pastes. 15 Drug Dosage and therapeutic window Therapeutic window Duration of action 16 Drug Dosage o For presentation of drug effect, an average blood serum concentration must be achieved prior to observation of drug’s desired effect. o Minimum effective concentration (MEC) is the minimum serum concentration of drug necessary to elicit a pharmacological action (drug effect). o Minimum toxic concentration (MTC) is the minimum serum concentration of drug above which dose related toxic side effects occur. o Duration: the period of the therapeutic effect of the drug which the concentration of the drug in plasma exceeds the minimum effective plasma concentration o Therapeutic window: a range of plasma drug concentrations assumed to exist over which the desired response is obtained, but toxic effects are avoided. 17 Drug Dosage Potent drugs Drugs that possess a narrow therapeutic window which means that the difference between MEC and MTC is so small that a tiny increment in the blood concentration causing serious toxic side effects. Drug dosage is few g (micrograms) to mg (milligrams). The daily dose of digoxin is 0.25 mg (250 g), and its therapeutic window ranges from 0.0006 to 0.0013 mg/liter. Paracetamol therapeutic window is 10 – 20 mg/liter whereas theophylline therapeutic window is 20 – 100 mg/Liter 18  Orphan drug ❑An orphan drug is a pharmaceutical agent that is developed to treat rare disorder or condition that affects fewer than 200,000 people. ❑Development of an orphan drug requires government assistance to encourage pharmaceutical industry to do research as those in pharmaceutical industry see that it would not be profitable to produce a drug treating rare disorder. 19