Pharmacology For Nurses Week 1

Pharmacology for Nurses Nur30 Mount Saint Mary’s College Associate Degree in Nursing Program Maggie Davis-Kendrick, RN,MSN

Core Concept in Pharmacology Characterization of: Pharmacology Is The Study of Medicine Derived from two Greek words Pharmakon – medicine drug Logos – study

Core Concept In Pharmacology Concepts Is a discipline devoted to patient therapy through the use of drugs Pharmacology utilizes concepts from human biology, pathophysiology, and chemistry

HX. Of Pharmacology One of the oldest form of healthcare, practiced in virtually every culture dating to antiquity Applying products to relieve suffering has been recorded throughout history by virtually every culture Modern pharmacology began in the early 19th century through the isolation of specific active agents from their complex mixtures

Regulations and Standards Created to protect the public from drug misuse Regulatory agency are responsible for ensuring that drugs and medical devices are safe and effective The regulatory agency responsible for ensuring that drugs and medical devices are safe and effective is the Food and Drug Administration (FDA)

Regulations and Standards Laws and other standards formed the basis of modern drug regulation used by agencies and organizations such as the FDA and the U.S. Pharmacopoeia-National Formulary Formulary – first standard commonly used by pharmacists Pharmacopoeia – medical reference summarizing standards of drug purity, strength and direction for synthesis

The FDA Branch of the U.S. Department of Health and Human Services Primary agency responsible for regulating drug safety Three branches control policies regarding drug therapies

Branches of the FDA The Center for Drug Evaluation and Research (CDER ) Exercises control over whether prescription drugs and OTC maybe used for therapy The Center for Biologics Evaluation and Research (CBER) Regulates use of biologics including serums, vaccines, and blood products

Branches of the FDA The Center for Food Safety and Applied Nutrition (CFSAN ) Regulates administration of herbal products and dietary supplements Drug regulations were created to protect the public from drug misuse The first drug laws were created by Congress to protect clients from wrongful therapeutic claims

Drug Legislation 1902- Biological Control Act to help standardize- the quality of serum and other blood-related products 1906 - Pure Food and Drug Act, gave the government power to control labeling of medicine 1912- Sherley Amendment prohibited the sale of drugs labeled with false therapeutic claims that were intended to defraud the consumer

Drug Legislation 1938 – Food, Drug, and Cosmetic Act, first law preventing the sale of drugs that had not been thoroughly tested before marketing 1994 – Dietary Supplement Health and Education Act passed in an attempt to control misleading industry claims

Stages of Drug Approval There are four stages of approval for therapeutic and biologic drugs Pre-clinical investigation – involves extensive laboratory research on humans and microbial cells cultured in the laboratory Clinical investigation – takes place in three different stages termed clinical phase trials

Stages of Drug Approval Stage II Clinical Phase Trials Longest part of drug approval process Essential component of drug evaluation Tests performed on healthy volunteers to determine proper dosage and assess for adverse effects

Clinical Phase Trials Large group of selected patients with the particular disease are given the medicine Clinical investigators from different medical specialists address concerns, if drug appears effective without serious side effects, maybe used immediately in special cases with careful monitoring

Stages of Drug Approval New Drug Application (NDA) with review Third stage FDA permitted six months to initially review a NDA Average review time 17-24 months Process suspended if rejected until concerns are addressed by the pharmaceutical company

Stages of Drug Approval Post Marketing Surveillance Final stage of drug approval process Begins after clinical trials and the NDA are completed Purpose is to survey for harmful drug effects in a large population Weighs therapeutic benefits versus its identified risks

Classification of Drug Therapeutic Clearly states what the drug does clinically Is the discipline dealing with the treatment of suffering and the prevention of disease Pharmacologic –refers to the way an agent work at the molecular, tissue, and body system Addresses a drug mechanism of action More specific than therapeutic Requires understanding of biochemistry and physiology Pharmacotherapy or Pharmacotherapeutics Is the application of drugs for the purpose of disease prevention and treatment of suffering

Classification of Drug Prototype - used to compare drugs within the same classification Original prototype not most widely used Newer drugs in same class maybe more effective Have more favorable safety profile and longer duration of action

Drug Names Three basic drug names Chemical Helpful in predicting a substances physical and chemical properties Often complicated and difficult to remember or pronounce Chemical name for diazepam: 7-chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one

Drug Names Generic Name is assigned by the U.S. Adopted Names Council Less complicated and easier to remember Only one generic name for each drug Less expensive

Drug Names Trade Assigned by company marketing the drug Sometimes called proprietary, product or brand name May have multiple names Selected to be short and easy to remember

Drug Names Generic substance Aspirin Diphenhydramine Ibuprofen Brand Name Anacin, Bayer, Excedrin Benadryl, Caladryl, Allerdryl Advil, Motrin, Midol

Generic/Brand Names Generic Name Conjugated Estrogen Digoxin Levothyroxine Sodium Wafarin Brand Name Equiv . Premarin Lanoxin Synthroid Coumadin

Classification of Therapeutics General categories Traditional Drugs - chemical agent capable of producing biological responses within the body (therapeutic or adverse) RAM Biologics - agents naturally produced in animals cells, microorganisms, or by the body itself Alternative Therapies - herbal supplements and certain techniques

Controlled Substances Drugs that have potential for abuse or physical and psychological dependence Use restricted by the Control Substance Act A special order form needed to obtain schedule II drugs There are five drug schedules of controlled substances

Schedule of Controlled Substance Schedule/Abuse Potential I/carries highest risk II/carries high potential III/moderate abuse risk IV/low abuse risk V/least abuse potential Therapeutic Use/ Example Limited or no use/heroin, LSD, Marijuana With prescription/MS, PCP, Cocaine With prescript./Codeine, ASA, Tylenol With prescript/Darvon, Librium, Valium Without prescription OTC

Methods of Dispensing Drugs Two major methods Purchase of prescriptions drugs with a physician’s order Purchase of over the counter (OTC) drugs which do not require a physician’s order There are advantages and disadvantages to both methods of dispensing

Principles of Drug Administration Rights of Drug Administration Right patient Right medication Right dose Right route Right time Right documentation

Principles of Drug Administration Additional Rights Right to refuse Right to receive medication education Right preparation

Principles of Drug Administration Three Checks of medication administration Checking the medication with the medication administration record (MAR) when removing it from its stored location Checking the medication when preparing it Checking the medication before administering it to the patient.

Principles of Drug Administration Abbreviations Table 4.1, Pg. 31 text Front cover pg. Drug Calculation book ac before meal Po or per os – by mouth pc – after meals mEq – milliequivalent gtt - drop hs – hour of sleep, at bedtime

Principles of Drug Administration Do not use U or u IU q.d. or QD q.o.d. or QOD MS MSO4 Zero after decimal point (1.0) Use instead Unit International Unit Daily Every other day Morphine Morphine sulfate 1

Principles of Drug Administration Do not use MgSO4 mg TIW or tiw AS AD AU No zero before decimal dose (0.5mg) Use instead Magnesium Sulfate Micro gram Three times weekly Left ear Right ear Both ears .5mg

Principles of Drug Administration Time Schedule ASAP – as soon as possible STAT – immediately Single – one time dose Routine – daily dose Standing – parameters left to follow PRN – when needed Drug Orders Clonidine .2mg po twice daily, hold for SBP<100

Principles of Drug Administration Drug Orders Vancomycin 750mg IV stat, followed by Gentamycin 1gm IV Lasix 40mg IV now and daily PO Tylenol 650mg po or pr, q 4hr prn temp. > 101 or mild pain

Principles of Drug Administration Time Schedules (military time) Daily or q am 0900 Twice daily 0900 1700 Three times daily 0900 1300 1700 Four times daily 0900 1300 1700 2100 Every pm 1700

Principles of Drug Administration Time Schedules (military time) Every hs (noc) 2200 Every 4 hours 0001 0400 0800 1200 1600 2000 Every 6 hours 0001 0600 1200 1800 Every 8 hours 0001 0800 1600 Every 12 hours 0600 1800

Principles of Drug Administration Documentation If medication refused or omitted and reason Any assessment Dosage and time administered Medication name and your signature Example: Tylenol 650mg pr (rectally) given for temp. 101.6 orally at 1600. M. Davis-Kendrick RN

Principles of Drug Administration Nursing Management Assumes great responsibility for drug administration Firm knowledge of drug Name and classification Intended or proposed use Effects on body Contraindication/special consideration Side effects

Principles of Drug Administration Nursing Management Why prescribed for this patient How supplied by pharmacy How is medication to be administered with dosage ranges What nursing process consideration related to medication apply to this particular patient

Routes of Drug Administration Enteral

Routes of Drug Administration Enteral Includes drugs given orally and those administered through nasogastric or gastrostomy tubes The sublingual and buccal routes are less commonly used enteral routes, dissolved directly into blood stream Is the most common, convenient, and usually, the least costly of all the routes

Routes of Drug Administration Enteral Tablets Maybe formulated to release the drug in a steady controlled manner Maybe scored for individual dosage, Maybe enteric-coated (EC) to dissolve in alkaline environment of sm. intestines Sustained- Release also called extended –release (XR), long acting (LA), or slow-release (SR) Do not crush EC or slow releasing tablets

Routes of Drug Administration Enteral Capsules Drug encased in shell of hard or soft gelatin Also comes extended release Extended-release capsules must not be opened Sublingual Placed under tongue and allowed to dissolve Result in a rapid onset of action

Routes of Drug Administration Enteral Buccal Placed in oral cavity between gums and cheeks Mucosa less preamble than sublingual Slower absorption than sublingual Preferred over sublingual for sustained release

Routes of Drug Administration Troches (lozenge) Commonly used to achieve local effect Held within the mouth until dissolved NGT/GT Useful if patient unable to swallow Medication is crushed or dissolved

Routes of Drug Administration Enteral Do not crush sustained release drugs or EC If tube connected to suction, hold for 30 minutes after giving medication If drug interferes with tube feeding hold feeding for 1 hour before and 2 hours after

Routes of Drug Administration Enteral Advantages Safe Convenient Least expensive Disadvantages Patient must be alert and able to swallow Need to stay until medicine is taken Greater chance for refusal and non compliance

Routes of Drug Administration Enteral Nursing Consideration Assess patient level of consciousness Assess allergies Monitor vital signs or lab result Perform the 5 rights of administration and The three checks before administering medication Documentation

Routes of Drug Administration Topical Application Instillations and irrigations –applied into body cavity or orifices These include the eyes, ears, nose bladder, rectum and vagina Inhalations – drugs applied to the respiratory tract by inhalers, nebulizers, or positive pressure breathing machines

Routes of Drug Administration Topical Transdermal Effective way of delivering specific amounts of medications Patches are changed/rotated on a regular basis Slow release and absorption Ophthalmic Used to treat local conditions of the eye and surrounding structure Available in the form of irrigation, drops, ointments, and medicated disks

Routes of Drug Administration Topical Otic Used to treat local conditions of the ear and auditory canal Includes eardrops and irrigations Perform carefully on infants and young children to avoid injury to sensitive structures of the ear Nasal Used for both local and systemic drug administration Drops or sprays often used for their local astringent effect which is to shrink swollen mucous membranes

Routes of Drug Administration Topical Vaginal Used to treat local vaginal infections, and to relieve pain and itching Inserted in suppositories, creams, jellies, or foam Rectal Used for either local or systemic administration Normally in suppository form Slowest rate of absorption

Routes of Drug Administration Parenteral Dispensing of medications via a needle Usually into the skin layers, subcutaneous tissue, muscles or veins Advance deliveries include into arteries, body cavities and organs Aseptic technique must be strictly applied

Routes of Drug Administration Parenteral Intradermal (ID) ID administered into the dermis (1 st layer of skin) Easily absorbed because of more blood vessels Usually for allergies, TB, anesthetic, or prior to IV insertion Limited to small volumes (0.1 to 0.2ml) Use only 25 or 27 gauge needle Inject into non-hairy skin surfaces (inner forearm )

Routes of Drug Administration Parenteral Subcutaneous (sub-q, SC, SQ) Administered into fatty tissue Less absorption than IM, distributed through capillaries Insulin, heparin, vitamins, some vaccines and narcotics Sites used are upper, lateral arms, anterior thigh, abdomen and mid back Doses small in volume (0.5 – 1cc) per injection

Routes of Drug Administration Parenteral Subcutaneous (sub-q, SC, SQ) Not necessary to aspirate Rotate sites TB and Insulin syringes are not interchangeable Use 5/8 inch needle Size of individual determines angle of injection (45 vs. 90 degree angle)

Routes of Drug Administration Parenteral Intramuscular (IM) Delivers medication injected into a certain muscle Onset of action more rapid than SQ because of rich blood supply Many are dry power and must be reconstituted before administration

Routes of Drug Administration Parenteral Intramuscular (IM) Most common sites Deltoid volume not to exceed 2 ml Small volume vaccines 1” needle

Routes of Drug Administration Parenteral Intramuscular (IM) Most common sites Dorsogluteal Up to 3ml/injection 1-1.5” needle Aspirate Inject slow & smooth

Routes of Drug Administration Parenteral Intramuscular (IM) Ventrogluteal Preferred site Contains no large vessels or nerves Suitable for children and infants over seven months

Routes of Drug Administration Parenteral Intramuscular (IM) Rectus femoris Used for infants Vastus lateralis Middle third used for injection Used most often in children

Routes of Drug Administration Intravenous

Routes of Drug Administration Intravenous Administration (I.V.) Direct delivery into systemic circulation, bypasses absorption process Rapid onset of action Allows large volumes to be given Acceptable when no other route possible

Routes of Drug Administration Intravenous Administration (I.V.) Three Basic Types Large volume infusion For maintenance, replacement or supplement Mixture of compatible drugs Intermittent infusion Intravenous Piggy Back (IVPB) Used to instill adjunct medication (analgesic, antibiotics )

Routes of Drug Administration Intravenous Administration (I.V.) Three Basic Types IV Bolus or IV Push Concentrated dose delivered via syringe Monitor closely for adverse reaction May take several minutes depending on the drug

Pharmacokinetics/ Pharmacodynamics Molecules Receptor Sites

Pharmacokinetics Derived from the root words Pharmaco – medicine Kinetics – movement or motion Focuses on the movement of drugs throughout the body after they are administered Deals with how the body metabolizes and excretes drugs

Pharmacokinetics Describes the barriers that drugs must penetrate to achieve therapeutic success Physiological properties of plasma membranes determine movement of drugs throughout the body

Pharmacokinetics Drugs primarily use two processes to cross body membranes Diffusion or Passive transport Movement of chemical from area of higher concentration to lower concentration Active transport Against a concentration or electrochemical gradient

Pharmacokinetics Plasma membrane consist of lipid bilayer with proteins and other molecules interspersed in the membrane This lipophilic membrane is relatively impermeable to large molecules, ions, and polar, molecules Drugs that are small, uncharged, and lipid soluble are distributed more completely than those that are large, ionized, and water-soluble These physical characteristic have direct application on pharmacokinetics

Pharmacokinetics The Processes of Pharmacokinetics Absorption Movement of the drug from it’s administration site into systemic circulation Many factors affect drug movement Rate of Dissolution- how fast the drug dissolve Surface Area- larger surface area = faster absorption Blood Flow: Greater blood flow = faster absorption Lipid Solubility- High lipid solubility = faster absorption pH Partitioning - ionize in the blood and not at the site of administration

Pharmacokinetics Pharmacokinetics Processes Distribution Represents how drugs are transported throughout the body Variables affecting distribution Lipid solubility Degree of ionization Plasma protein binding The blood-brain barriers Fetal-placental barrier

Pharmacokinetics Pharmacokinetics Processes Distribution Amount of blood flow to body tissue is the main factor determining distribution Cardiac output Body composition( amt. of adipose tissue) Presence and degree of vessel constriction or dilatation

Pharmacokinetics Pharmacokinetics Processes Metabolism (Biotransformation ) Is a process that changes a drug’s activity and makes it more likely to be excreted. Alters drug structure usually in the liver First-Pass Effect- Hepatic inactivation of certain oral drugs Metabolic enzymes in the liver are less active in infants and geriatric patients

Pharmacokinetics Processes Excretion Elimination of drug from circulation The main organ involved with excretion is the kidney Drugs are eliminate from the body by Kidney via the urine Lungs via exhaled air Sweat glands via perspiration Tears via crying Mammary glands via breast milk and Biliary system

Pharmacokinetics Plasma Concentration The therapeutic response of most drugs are related to their plasma concentration Minimum – amount required to produce therapeutic effect Therapeutic -lies between the minimum effective level and the toxic level. Toxic – result in serious adverse effects

Pharmacokinetics Plasma Concentration Plasma half-life Represents the duration of action for most drugs The length of time the body takes to reduce the plasma level of a drug to 50% of its peak value Loading dose Higher amount of drug Given once or twice to Quickly induce a therapeutic response

Pharmacokinetics Plasma Concentration Equilibrium state The amount of drug administered is equal to the amount excreted Equilibrium state may be reached faster through the use of loading doses Maintenance dose Given to keep plasma concentration in therapeutic range

Pharmacodynamics Is comprised of the root words Pharmco – medicine Dynamics – change ! Pharmacodynamics – the mechanism by which drugs produce biochemical and physiologic changes in the body The differences in patient responses to medications

Pharmacodynamics Frequency Distribution Curve Represents drug action in a specific patient population The middle of the curve represents a drug’s median effective dose Used to represent safety of a drug Therapeutic Index Is a value representing the margin of drug safety Equals median lethal dose divided by median effective dose Larger the difference the greater the therapeutic index

Pharmacodynamics Potency and Efficacy Potency - the dose of medication required to elicit a particular response Efficacy - the magnitude of maximal response to a drug Efficacy of a drug is more important to the patient and nurse than the potency

Pharmacodynamics Drug Receptor Interaction Used to explain the mechanism of action of many medications Majority of receptors are proteins located on the plasma cell membrane Some drug responses are nonspecific and do not involve direct receptor interaction

Pharmacodynamics Drug Receptor Interaction Drugs compete with endogenous substances and other medications for cellular receptors Agonist - are drugs that bind to a receptor and cause effects that mimic normal cell activities . Partial agonist – produces a weaker or less efficacious, response than an agonist Antagonist - are drugs that bind to a receptor and inhibit normal cell activity

Pharmacodynamics Pharmacology of the Future Likely be customized to match the genetic make-up of each patient Pharmacogenetics - application of genetics to pharmacology with the objective of individualizing therapy

Pharmacotherapy across the Lifespan Pregnancy Conducted only when the benefits to the mother outweigh the potential risks to the fetus Pregnancy Categories guide the practitioner in prescribing drugs for these patients Pregnancy Categories have been developed by the FDA to assess potential risk to the fetus

Pharmacotherapy across the Lifespan Pregnancy Drugs and other substances can appear in breast milk and affect infants Refer to FDA Pregnancy Categories (table 7.1 pg.69 text) Infancy (birth 12 months) Directed toward safety Administer oral medication slowly

Pharmacotherapy across the Lifespan Infancy (birth 12 months) For suppositories hold buttocks together for 5-10 minutes Vastus lateralis preferred site for IM injection Medication prescribed in milligrams per kilogram per day (mg/kg/24h)

Pharmacotherapy across the Lifespan Infancy (birth 12 months) Alternate method for calculating dosage is to use the infants body surface area (BSA ) BSA refers to the total area exposed Derived from height and weight Two formulas used Formula using metric system Weight (kg) x Height (cm) 3600

Pharmacotherapy across the Lifespan Infancy (birth 12 months) B. Formula using pounds and inches Weight (lb) x Height (in ) 3131 BSA written in square meter (m2) Maybe used to double check orders for safe dosage

Pharmacotherapy across the Lifespan Toddlers (1-3) Major concern, sense of curiosity Can swallow liquid, maybe able to solid medication IM injection given in the vastus lateralis IV may use scalp or feet

Pharmacotherapy across the Lifespan Preschool (3-5) Dorsogluteal site used for IM after 1 year of walking Peripheral veins used for IV injections Often resist medication School Age (6-12) Begin to realize the benefits of medications and the reasons why medications are needed

Pharmacotherapy across the Lifespan School Age (6-12) Give the child a sense of control over drug administration At the same time be firm and giving the child praise for cooperation Can take chewable tablets, may swallow tablets or capsules Ventrogluteal site preferred for IM

Pharmacotherapy across the Lifespan Adolescence Respect need for independence and privacy Concerned with physical appearance and peer approval Indications for pharmacotherapy Skin conditions Headaches Menstrual irregularities Sports injuries

Pharmacotherapy across the Lifespan Young (18-40) and Middle (40-65) Adulthood Generally need little pharmacotherapy Complications associated with pregnancy are of major concern Cardiovascular concerns become important Use of antidepressants and antianxiety agents are prominent in the over-50 population

Pharmacotherapy across the Lifespan Older Adults Take more medications (polypharmacy) and experience more adverse drug events than any other age group Must make accommodations for age-related changes in physiological and biochemical functions With numerous physical challenges, which become targets for pharmacotherapy

Pharmacotherapy across the Lifespan Older Adults Changes in liver and kidney function make pharmacotherapy more risky Cardiovascular disease becomes a major indication for pharmacotherapy For drug therapy to be successful must make accommodations for age-related changes in physiological and biochemical functions

Legal and Ethical Issues Ethics Branch of philosophy dealing with the moral principles that guide a person’s behavior or conduct Are learned early in life through religious affiliations, family, role models, and peers

Legal and Ethical Issues Moral Principles such as beneficence, non-maleficent behavior, veracity, autonomy, justice, and fidelity are necessary in medication administration When making ethical decisions in clinical practice, the nurse uses fundamental moral principles

Legal and Ethical Issues Three most important principles Beneficence - promote the most good for the patient Non-maleficent – obligation not to harm the patient Autonomy - allowing the patient the informed right to choose the course of their care

Legal and Ethical Issues Legal Nurse Practice Act Defines the scope of practice for professional nursing Defines the standard of care for practicing nurses State the minimum competency for proficiency in nursing Documentation of medication administration, including any errors, should be completed immediately

Legal and Ethical Issues Legal Medication Errors A preventable error that may cause or lead to an adverse reaction can result in serious injury to the patient and litigation for the nurse and healthcare agency

Legal and Ethical Issues Legal It is the ethical and legal responsibility of the nurse to report any medication errors Documentation necessary for patient safety Finding strategies to prevent of medication errors involves many different processes, including the nursing process

Nursing Process Is a systematic method of problem-solving and consists of clearly defined steps Assessment First step in the nursing process Baseline data gathered (subjective, objective) Assessment includes health history information, physical assessment data, lab values and other measurable data Includes an assessment of medication effects: therapeutic, side or adverse effects

Nursing Process Nursing Diagnosis Are developed after an analysis of the assessment data Diagnoses are focused on the patient’s problems or potential problems Begin by addressing problems that pose immediate threats to the patient’s health

Nursing Process Goal Developed from the nursing diagnoses Focus on what the patient will be able to do or achieve Outcomes Objective measures of goals Define what the patient will do Under what circumstances and time frame Goals and outcomes are prioritized to address immediate need first

Nursing Process Goals and outcomes may be developed for short-term or long-term, depending on the specific situation Planning Links strategies or interventions to goals and outcomes Interventions Aimed at returning the patient to an optimum level of wellness and limiting adverse effects

Nursing Process Interventions Key components of implementation include monitoring and documentation of drug effects, and patient education Monitoring drug effects is a primary intervention Patient teaching is a vital component( considered primary role Documentation of both therapeutic and adverse effects is complete during this phase

Nursing Process Evaluation Final step of the nursing process Considers the effectiveness of interventions at meeting goals and outcomes Evaluation begins a new cycle as new assessment data is gathered and analyzed Nursing diagnoses are reviewed or rewritten, goals and outcomes refined, and new interventions are implemented

System of Measurement Include the metric, apothecary, and household systems

System of Measurement Metric Preferred system of measurement Also known as the International System of Units (SI) Basic unit of mass (weight) is the gram Basic unit of volume (capacity) is the liter Milliliter (mL) and cubic centimeter (cc) are used interchangeably

System of Measurement Metric Equivalents frequently used (memorize ) Weight 1mg (milligram) = 1000mcg (microgram) 1g (gram) = 1000 mg (milligrams) 1 kg (kilogram) = 1000 g or Gm (grams) = 2.2 lbs Volume 1L (liter) = 1000cc or 1000 ml (milliliters)

System of Measurement Apothecary

System of Measurement Apothecary Apothecary means “Pharmacist” Imprecise, old English system of measurement Grain, basic unit of weight Basic unit of volume is the minim, which = one drop (gtt)

System of Measurement Apothecary Abbreviation or symbol usually written before amount or quantity –ex gr 60 = 1 dram Measures based on the minim Fluidram (fl. dr.) Fluid ounce (fl. Oz.) Pint (pt.) Quart (qt.)

System of Measurement Household

System of Measurement Household Least accurate system of measurement Measurements approximate Becoming increasingly more important with the trend toward home health care

System of Measurement Household Household Measures Tablespoon (Tbs or T) Teaspoon (tsp or t) Drop (gtt)

System of Measurement Units of Measurements Measures drugs in terms of their action Vitamins, antibiotics, insulin and heparin are measured in units Label indicates units per ml No conversion exists for units

System of Measurement Milliequivalent (mEq) Measures chemical combining power of electrolytes such as potassium (K+) Specific to medication used Has no conversion to another system

System of Measurement Dosage measured in percentage Commonly used in IV solutions D5W, D5 ½ NS, D10, .45NS, 0.9 NS Often used with metric measures Means part per hundred or number of grams of drug per 100ml of solution Often no conversion is necessary (give 10ml of 10% calcium gluconate )

System of Measurement Metric House 1ml 15-16gtts 4-5cc 1tsp or 15-16ml 1Tbs or 30-32ml 2Tbs 240-250 1gl or cup 500ml 2gls or cups 1L 1qt, or Apothecary 15-16minims 1 fluid dram 4 fluid ounces 8fl. dr or 1oz 8 oz or ½ pt. 1pint 32ounces or 1qt

System of Measurement Metric 1mg 60-64mg 300-325mg 1kg =2.2lbs 1gram Apothecary 1/60 gr 1gr 5grs 15-16grs

System of Measurement Conversion between and within systems 1 g = 1000mg 1000mcg 2.2lbs 1T = 0.5L 15mL 3tsp 1kg = 1000g 1dr 2.2lb 1cc = 500mL 1L 1mL

References Adams, M, Josephson, D. & Holland, L. (2005). Pharmacology for Nurses: A pathophysiologic approach, Pearson Prentice Hall, New Jersey Aschenbrenner,D & Venable, S (2006). Drug Therapy in Nursing. 2 nd Edition, Lippincott Williams & Wilkins, Brown, M & Mulholland, J. (2004). Drug Calculations: Process and Problems for clinical Practice 7 th Edition , Mosby, St. Louis , Missouri

References (2004).Straignt A’s in Pharmacology, Lippincott Williams & Wilkins (2005).Dosage Calculations Made Incredible Easy, 3 rd Edition, Lippincott Williams & Wilkins (2005).Nursing Pharmacology Made Incredible Easy, Springhouse www.crnasomeday.com/pharmacology.htm

Pharmacology For Nurses Week 1

In this document