Pharmacologic Principles Chapter 1, 2, 3

Understanding Nurses must understand both + and – effects of drugs Pharmacotherapeutics –u–use of drugs and the clinical indications for drugs to prevent and treat diseases Pharmacodynamics – study of what the drug does to the body Pharmacognosy –n–natural drug sources

Drug Names Chemical Trade –Patented –Belongs to a company Generic –Commonly known –Less expensive

Phases of Activity Pharmaceutical –Administered –Dissolves or disintegrates Pharmacokinetic –Absorbed –Sent to tissues –Metabolized (used) –Excreted (disposed of) Pharmacodynamic –Ways drug affects the body

First-Pass Effect metabolism of a drug by the liver before its systemic availability AKA Bioavailability Amount of the drug that makes it into circulation

Drug Transport How does the drug get from point A to point B? Parenteral Liver Circulation OR Gastric Liver Circulation

Action Curve Time from delivery to start of therapeutic effect = Onset of Action From delivery to maximum therapeutic effect = Peak Effect Total amount of time therapeutic effect is notable = Duration of Action

Mechanism of Action Receptor –Designated site accepts drug Enzyme –Chemical reaction “glues” drug to site Nonspecific –Drug stimulates changes in cell to allow it in

Chemical Bonds Agonists Antagonists Partial-agonist or Agonist-Antagonist

Drug Excretion Organs: liver, kidneys, intestines Kidneys have primary responsibility Breakdown by liver makes kidney’s job easier Some drugs are eliminated through bowels

Considerations Therapeutic Index – difference between good & dangerous effects Amount of drug circulating = concentration Patient condition – liver & kidney health, age, GI function Tolerance or Dependence Interactions

Drug Misadventures Adverse Drug Event (ADE) –Adverse Drug Reaction (ADR) Caused by factors inside patient’s body Allergy, unknown, kidney or liver disease Not able to be controlled –Medication Error Most common type of event Related to administration, dispensing, prescribing

Life Span Pediatrics –Very young have immature livers - can’t process drugs as well –Adult drugs may be passed through breastmilk – check safety if mother is breastfeeding –Dosage based on mg/kg for safety

Life Span, con’t. Adult –Careful of interactions with Other drugs Herbal substances –Risk for noncompliance d/t ‘undesirable’ effects

Life Span, con’t. Elderly –Be aware of possible diminished: liver or kidney function – monitor lab tests Cardiac function – be aware of test results Digestive changes –Assess ability to read labels & open containers –Assess for potential safety issues – meds may cause drowsiness or diminished response

Nursing Process Assess –Patient needs –Patient & family understanding –Patient (and family) physical abilities Plan (Goal) –Include patient & family –Tailor to patient/family needs –Include social services, prn

Nursing Process, con’t. Implement –Regular re-assessments –Monitor for changes –Observe for therapeutic affects Evaluate –Is plan working? –Does it need modifying? –What can change?

5 Rights Basic to medication administration –Right Drug –Right Dose –Right Time –Right Route –Right Patient

Errors IF a med error occurs –Admit the error – don’t try to cover it up –Notify physician –Take emergency/first aid measures, prn –Complete proper reporting form NEVER record terms “by mistake”, “on error”, “unintentionally” DO NOT record error in patient chart