Pharmacology Introduction PDF

Learning Objectives At the end of this chapter the student will be able to: 1. Define various terminologies used in Pharmacology 2. Understand pharmacodynamics and pharmacokinetics (absorption, distribution, metabolism and excretion) of drugs 3. Understand theoretical pharmaco...

Learning Objectives At the end of this chapter the student will be able to: 1. Define various terminologies used in Pharmacology 2. Understand pharmacodynamics and pharmacokinetics (absorption, distribution, metabolism and excretion) of drugs 3. Understand theoretical pharmacokinetics like half-life, order of kinetics, steady state and plasma concentration 4. Understand drug safety and effectiveness like factors affecting drug action and adverse drug reactions  Definitions Pharmacology: from Greek , pharmakon, "drug"; logia, "the study of“ (study of the drug) The science that deals with effects of drugs on living system. It includes the history, source, physicochemical properties, dosage forms, methods of administration, absorption, distribution, mechanism of action, biotransformation, excretion, clinical uses and adverse effects of drugs Drug `Any substance or product` that is used or intended to be used to modify physiological systems or pathological states for the benefit of the recipient. A substance used in the prevention, treatment or diagnosis of disease.  Pharmacokinetics (PK): Study of the absorption, distribution metabolism and excretion (ADME) of drugs (“ What the body does to a drug ”) Pharmacodynamics (PD): The study of the biological and therapeutic effects of drugs (“What the drug do to the body”) Pharmacotherapeutics: It deals with the proper selection and use of drugs for the prevention and treatment of disease Toxicology: Toxicology is the branch of pharmacology dealing with the "undesirable" effects of drugs on biological processes  Clinical pharmacology: Is the systematic study of a drug in humans, both in healthy volunteers and patients. It includes the evaluation of pharmacokinetic and pharmacodynamics data, safety, efficacy, and adverse effects of a drug. Pharmacy: It is the branch of science that deals with the preparation, preservation, compounding and proper use of drugs  Food & Drug Administration (FDA) The federal agency responsible for the safety and efficacy of all drugs in the US. It is also responsible for food and cosmetics. Adverse or “Side-Effect” An unintended action of a drug. Results from a lack of specificity of drug action. All drugs are capable of producing adverse effects.  Drug Names Chemical name The drug’s chemical composition and molecular structure Generic name (nonproprietary name) Name given by the United States Adopted Name Council Trade name/ Brand name/Product (proprietary name) The drug has a registered trademark; use of the name restricted by the drug’s owner (usually the manufacturer) Chemical Name Generic Name/ Brand Name/ Non- Proprietary Proprietary Name Name Isobutylphenylpr- Ibuprofen Trufen, Advil, opionc acid Ultrafen Acetaminophen Paracetamol Otamol, Acamol, Sedamol, Aminobenzyl Ampicillin Ampipharm Penicillin To avoid confusion: it’s best to use a drug’s generic name Grouping of drugs: Pharmacologic class (or family): – drugs that share similar characteristics – Example: beta-adrenergic blockers are an example of a pharmacologic class. Therapeutic class: – groups drugs by therapeutic use – Example: Antihypertensives Principles of Prescription Writing  Definition A prescription is a written, verbal, or electronic order from a practitioner or designated agent to a pharmacist for a particular medication for a specific patient.  The “Five Rights” of Medication Administration ❖ Right drug ❖ Right dose ❖ Right time ❖ Right route ❖ Right patient  Prescription Formatting Heading Body Closing  Tablets - tab Capsule – cap Syrup – syr Suspension – susp Injection – Inj Metered dose inhaler – as such Lotion – as such  PO: by mouth PR: per rectum IM: intramuscular IV: intravenous ID: intradermal IN: intranasal TP: topical SL: sublingual BUCC: buccal IP: intraperitoneal  Controlled Substances Definition - a prescription drug whose use and distribution is tightly controlled because of its abuse potential or risk Regulation is more strict