Pharmacology Basics PDF

PHARMACOLOGY Presented By : Natasha Kay V. Chan, RN, MN SUNN| 2024  HUMAN BODY AND CHEMICAL REACTIONS Human body operates through complex chemical reactions and processes. Pharmacology: study of biological effects of chemicals. Drugs: chemicals introduced to th...

PHARMACOLOGY Presented By : Natasha Kay V. Chan, RN, MN SUNN| 2024  HUMAN BODY AND CHEMICAL REACTIONS Human body operates through complex chemical reactions and processes. Pharmacology: study of biological effects of chemicals. Drugs: chemicals introduced to the body to cause changes. Body processes handle and eliminate drugs, impacting chemical reactions.  PHARMACOLOGY BASICS Pharmacokinetics Pharmacodynamics Absorption, distribution, The biochemical and metabolism, and physical effects of drugs excretion of a drug. and the mechanisms of drug actions Pharmacotherapeutic s The use of drugs to prevent and treat disease  DRUG NAME Chemical Name Is a scientific name that precisely describes its anatomic and molecular structure Generic Name Abbreviation of the chemical name  DRUG NAME Trade name Brand name or Proprietary name Selected by the drug company selling the product These are protected by copyright The symbol ® indicates the name is registered by and restricted to the drug manufacturer  DRUG NAME Example Chemical Name ⚬ 7-chloro-1, 3-dihydro-1, methyl-5- phenyl-2h-2 Generic Name ⚬ Diazepam Brand Name ⚬ Valium WHERE DRUG COMES FROM Natural Syntheti Resources Plants c impurities found Free from the Animals in natural Minerals substances  DRUG ADMINISTRATION ROUTES Buccal, Sublingual. Translingual Buccal (pouch between the cheek and gum) Sublingual (under the tongue) Translingually (on the tongue) Gastric Allows direct installation of medication into the GI system of patients who can’t ingest the drug orally  DRUG ADMINISTRATION ROUTES Intravenous the I.V. route allows injection of substances (drugs, fluids, blood or blood products, and diagnostic contrast agents) directly into the bloodstream through a vein administration can range from a single dose to an ongoing infusion delivered with great precision  DRUG ADMINISTRATION ROUTES Oral This is usually the safest, most convenient, and least expensive route; drugs are administered to patients who are conscious and can swallow Rectal and vaginal Suppositories, ointments, creams, gels, and tablets may be instilled into the rectum or vagina to treat local irritation or infection; some drugs applied to the mucosa of the rectum or vagina can  DRUG ADMINISTRATION ROUTES Respiratory Drugs that are available as gases can be administered into the respiratory system; drugs given by inhalation are rapidly absorbed, and medications given by such devices as the metered-dose inhaler can be self-administered, or drugs can be administered directly into the lungs through an endotracheal tube in  DRUG ADMINSITRATION ROUTES Drugs may also be given as specialized infusions injected directly into a specific site in the patient’s body such as: Epidural infusion (into the epidural space) Intrathecal infusion (into the cerebrospinal fluid) Intrapleural infusion (into the pleural cavity) Intraperitoneal infusion (into the peritoneal cavity) Intraosseous infusion (into the rich vascular network of a long bone) Intraarticular infusion (into a joint).  DRUG FORMS Solid Forms Pill s Drugs shaped spherical to be swallowed Tablet Powders compressed into disc-like Suppositories form Drugs mixed with a waxlike base that melts at body temperature Capsules Gelatin containers filled with powders or tiny pills  DRUG FORMS Liquid Forms Solutions Water or oil based Tinctures Prepared using alcohol extraction Suppositories process Drugs mixed with a waxlike base that melts at body temperature Suspensions Preparations in which the solid does not dissolve in the solvent  DRUG FORMS Liquid Forms Emulsions Suspensions with an oily substance in the Spirits solvent Solution of a volatile drug in alcohol Elixirs Alcohol and water solvent often with flavouring Syrups Sugar, water, and drug solutions  PHARMACOKINETICS Kinetics refers to movement. Pharmacokinetics deals with a drug’s actions as it moves through the body. Therefore, pharmacokinetics discusses how a drug is: ⚬ Absorbed (taken into the body) ⚬ Distributed (moved into various tissues) ⚬ Metabolized (changed into a form that can be excreted) ⚬ Excreted (removed from the body).  PHARMACOKINETICS This branch of pharmacology is also concerned with a drug’s onset of action, peak concentration level, and duration of action  ABSORPTION Absorption Drug absorption covers a drug’s progress from the time it’s administered, through its passage to the tissues, until it reaches systemic circulation. On a cellular level, drugs are absorbed by several means—primarily through active or passive transport.  DISTRIBUTION Distribution Drug distribution is the process by which the drug is delivered from the systemic circulation to body tissues and fluids. Distribution of an absorbed drug within the body depends on several factors: ⚬ blood flow ⚬ solubility ⚬ protein binding  METABOLISM Metabolism Drug metabolism, or biotransformation, is the process by which the body changes a drug from its dosage form to a more water-soluble form that can then be excreted. Drugs can be metabolized in several ways: Most drugs are metabolized into inactive metabolites (products of metabolism), which  METABOLISM Metabolism Other drugs are converted to active metabolites, which are capable of exerting their own pharmacologic action. Active metabolites may undergo further metabolism or may be excreted from the body unchanged  EXCRETION Excretion Drug excretion refers to the elimination of drugs from the body. Most drugs are excreted by the kidneys and leave the body through urine. Drugs can also be excreted through the lungs, exocrine (sweat, salivary, or mammary) glands, skin, and intestinal tract.  PHARMACODYNAMICS The study of the drug mechanisms that produce biochemical or physiologic changes in the body. The interaction at the cellular level between a drug and cellular components, such as the complex proteins that make up the cell membrane, enzymes, or target receptors, represents drug action. The response resulting from this drug action is the drug effect. PHARMACOTHERAPEUTICS The use of drugs to treat disease. When choosing a drug to treat a particular condition, health care providers consider not only the drug’s effectiveness but also other factors such as the type of therapy the patient will receive. Not all therapy is the same  DRUG INTERACTIONS Drug interactions can occur between drugs or between drugs and foods. They can interfere with the results of a laboratory test or produce physical or chemical incompatibilities. The more drugs a patient receives, the greater the chances that a drug interaction will occur.  DRUG INTERACTIONS Potential drug interactions include: ⚬ Additive effects ⚬ Potentiation ⚬ Antagonistic effects ⚬ Decreased or increased absorption ⚬ Decreased or increased ADVERSE DRUG REACTIONS A drug’s desired effect is called the expected therapeutic response. An adverse drug reaction (also called a side effector adverse effect), on the other hand, is a harmful, undesirable response. Adverse drug reactions can range from mild ones that disappear when the drug is discontinued to debilitating diseases that become chronic. Adverse reactions can appear shortly after starting a new medication but may become less TYPES OF MEDICATION ORDERS STAT ⚬ Needed immediately Single Order ⚬ Given only once PRN ⚬ Given as needed Standing Order ⚬ Written in advance carried out under specific circumstances