a drug that produces a response
a drug that blocks a response
a drug that reverses a response
related to absorption of the drug; it is the percentage of the administered drug that reaches systemic circulation
Blood-Brain Barrier is...
a barrier that allows for only fat-soluble medications to pass into the brain and the CSF
- t 1/2
- the time that it takes for 1/2 of the drug concentration to be eliminated
Loading Dose is...
a large initial dose that is used when an immediate response is desired to reach the drugs minimum effective concentration (MEC)
a substance administered to people for the dx, cure, tx and mitigation or prevention of disease
OTC Medications are...
over the counter medications
Drug Polymorphism is...
the effect of a drug action that varies from a predicted drug response because of individual genetic factors or hereditary influence
the study of the effects of chemical substances on living tissue
Plasma Protein Binding...
as drugs are distributed in the plasma, they are bound to different degrees. The portion of the drug that is bound is inactive bc it is not available to attach to receptors. The portion of the drug left is the free, active drug.
when a pt is taking many medications, prescribed or not, in an attempt to treat several disorders simultaneously
National Formulary (NF) is...
- how the drugs are made
- ie. the drug recipe book
Hospital Formulary is...
the drugs the hospital stocks and uses
Differentiate among the various names for drugs.
- ~provides and exact description of the medication composition and molecular structure.
- ~it describes the drugs chemical structure
- ~rarely used in practice
- ~the official name of the drug
- ~this name is not owned by any drug company and is universally acceptable
- ~most drugs are ordered by the generic name
~the name that is listed in the official publications
Trade or Brand names:
- ~the name under which the manufacturer markets the medication
- ~usually a registered trademark
Explain the purpose of drug classifications.
- ~the drug classification indicates the effect the medication has on the body system, the symptoms the medication relieves, or the medications desired effects
- ~usually each class contains more than one medication that can be prescribed
- ~a provider chooses a particular medication based on the clients characteristics, cost, efficiency, dosing frequency or prescribers experience with a particular medication
- ~a medication may belong to more than one classification. ie; aspirin is an analgesic, antipyretic and anti-inflammatory
- ~drugs are commonly classified by chemical structure, mode of action, physiologic action or therapeutic effect
Identify several references where the nurse can obtain information abt drugs.
- PDR (Physicians Desk Reverence)
- Pharmacology Textbooks
- Drug Guide Books
- Medication Package Inserts
Define and describe the Pharmaceutic phase of drug action.
Dissolution stage is the first stage of drug action. a drug needs to be in solution to be absorbed. Dissolution is when the drug, such as a tablet, disintegrated into smaller particles to dissolve in a liquid
Define and describe the Pharmacokinetic phase of drug action, including absorption, distribution, biotransformation and elimination.
the process of drug movement to achieve drug action
- the movement of drug particles by active transport (requires a carrier), passive transport (by diffusion) or pinocytosis (the cell engulfs the particle). the cell must be in a solution to be dissolved
- the process in which drugs become available to the body fluids and body tissues (plasma protein binding). the dispersal of the drug from the site of absorption to the site of action. influenced by pathophysiology, affinity of tissue and the protein binding
- after the med reaches it site of action, it becomes metabolized into a less active, or inactive form that is more easily excreted. this occurs under the influence of enzymes that detoxify, degrade and remove biologically active chemicals. most biotransformation occurs in the liver, some in the lungs, kidneys, blood and intestines
- after medications are metabolized, they are excreted from the body through the kidneys, liver, bowel, lungs and exocrine glands. the main route is through urine.
Define and describe the Pharmacodynamic Phase of drug action; including onset, peak and duration of action; receptors; therapeutic index and range; and peak and trough levels.
the effects of the drug on cellular physiology, biochemistry and the drugs mechanism of action. it can have a primary and secondary physiologic effect, or both. the primary effect is desirable; the secondary effect may be desirable or undesirable.
Onset-the time it takes to reach the minimum effective concentration (MEC) after the drug is administered
Peak-occurs when the drug reaches its highest blood plasma concentration
Duration of action- the length of time the drug has a pharmacologic effect
Receptors- are found on the glycocalyx of cell membranes; there are 4 types: 1. cell membrane w embedded enzymes; 2. ligand gated ion channels; 3. G protein-coupled receptor systems; 4. transcription factors
Therapeutic index- (TI) estimates the margin of safety of a drug using a ratio that measures the effective dose and the legal dose to attain a range of safe doses.
Therapeutic Range- a drug concentration in plasma should be b/t the MEC in the plasma for obtaining desired drug action and the minimum toxic concentration (MTC), the toxic effect.
Peak Drug Level- the highest plasma concentration of a drug at a specific time. normally 30 mins after it is administered
Trough Drug Level- the lowest plasma concentration of a drug and measures the rate at which a drug is eliminated. tested 0-15 minutes prior to the next dose.
Identify the variables that influence drug action.
- influence the absorption:
- route of administration
- ability of the medication to dissolve
- blood flow to the area of absorption
- body surface area
- lipid solubility of a med
- influence on distribution:
- membrane permeability
- protein binding effect
Define and describe the various types of drug action.
- Therapeutic Effect:
- the expected or predictable physiological response a medication causes
- Side Effects:
- unintended, secondary effets a medication predictability will cause, can cause injury or be harmless
- Adverse Effects:
- severe responses to medications
- Toxic Effects:
- when a medication accumulates in the blood bc of impaired metabolism or excretion. can have a lethal effect depending on the medications action
- Idiosyncratic Reactions:
- when medications cause unpredictable effects such as when the pt over/under reacts to the medication or if the reaction is opposite from the normal response
- Allergic Reaction:
- when a pt has an allergic response to a medication, its chemical preservatives or its metabolites. the med is an antigen epitope and the body's immune system reacts to it, it can be mild or severe
- Medication Interactions:
- when one medication modifies the action of another. not all action are undesirable; some meds in combination have a synergistic effect, ie, stronger together then when alone
Describe the following drug interactions and indicate nursing responsibilities of each.
- Drug-Drug Interactions:
- the effects of a combination of drugs may be >, =, or < the effects of a single drug. some drugs may compete for the same receptors , an adverse reaction may lead to toxicity or anaphylaxis. RN responsibilities include checking compatibility of all drugs the pt is taking
- Drug-Food Interactions:
- the effects of selected foods might speed up, delay or prevent absorption of certain drugs. prior to dispensing the drugs the nurse makes sure that the contraindicated foods/ beverages aren't consumed by the pt.
- Drug-Laboratory Interactions:
- serum electrolyte concentrations can be greatly affected by some drug therapies. ie. potassium
Discuss the effects of the following drug interactions. Additive, Potentiating/synergistic, inhibiting and antagonistic.
- a substance added intentionally, can enhance the effect of the drug
- the effect of two drugs combined is > the effect of the drugs being given separately
- the effect of one of the drugs slows down or stops the effects of the other
- drug blocks a response
Describe the following routes of administration for drugs and indicate advantages and disadvantages for each.
- Oral: by mouth
- Buccal: in the cheek
- Sublingual: under the tongue
- Topical: to the skin
- Otic: to the ears
- Rectal: to the anus
- Nasal: through the nose
- Ophthalmic: to the eyes
- Parenteral: Directly into the intestines
- Subcutaneous: under the skin
- Intramuscular: in the muscle
- Intradermal: in the skin
- Intravenous: in the vein
- Vaginal: through the vagina
- Inhalation: inhaled
- Transdermal: through the skin
Differentiate non specific drugs from non selective drugs.
Non-specific drugs are not specific to location of the receptors, they are specific to 1 type of receptor but will act wherever those receptors are located
Non-selective drugs act on different or multiple receptor sites
Describe the various forms of oral and topical preparations.
- liquids such as elixirs, emulsions and suspensions
- tablets, capsules, etc
- syrups, solutions
- creams, lotions, ointments and gels
- optic, otic
- vaginal, rectal
List the components of a complete medication order.
- pt name
- date and time the order is written
- name and dose of the medication
- route of administration
- time and frequency of administration
- MD signature
Define and indicate the rationale for the various types of medication orders.
- Pre-op: prior to sx
- PRN: as needed
- Routine: carried out until the prescriber cancels it by another dose or until a prescribed number of days elapses
- Single: a one time only order, given only once at a specific time
- Standing: same as routine order but may indicate a final date or number of tx doses
- Stat- : a single dose to be given immediately
Review the systems of drug measurements.
Identify nursing responsibilities in relation to "5 + 5 rights" and "3 checks" of safe medication administration.
- 5 Rights:
- 3 Checks of safe med admin:
- the medication order is complete and legible
- know the reason why the client is receiving the med
- check the drug label 3 times before administration
- at initial contact w the drug
- as the drug is being counted or measured
- before returning the container to storage
Discuss the nursing responsibilities associated with the administration of controlled substances.
in administering controlled substances, the RN must properly document the admin on a MAR.
Explain the RN's responsibilities in the event of a medication error.
a medication error is any event that could cause or lead to a pt receiving inappropriate medication therapy or failing to receive appropriate medication therapy. in the case of a medication error, it is the nurses responsibility to complete and incident report describing the nature of the incident
Discuss special considerations the RN makes in administering meds to the older adult.
- they may be polypharmacy so there is a high risk of medication reactions
- they may self prescribe meds bc of the various symptoms experienced; ie, pain, constipation, insomnia
- the use of OTC meds whose ingredients can cause undesirable side effects or adverse reactions
- misuse of medications, overuse, underuse, erratic use or contraindicated use
- noncompliance, deliberate misuse of medication, they dont stick to the regimen bc of ineffectiveness or uncomfortable side effects
Identify nursing dx associated with medication administration.
Knowledge Deficit: the RN implements an extensive teaching plan and f/u. the client must be taught the medications purpose, importance of a regular dose schedule, proper administration and the side effects to gain compliance
High Risk for Injury r/t adverse drug event: stop the administration of the drug and notify the pt's md
What are some suggestions for safe medication administration that the RN can offer to the pt who is going home?
- collaborate with the pt's family and friends
- make sure they know how and where to administer the medication
- make sure that they know how to read the medication label
- make sure that they are able to self administer the meds
In what ways do the physiological changes of age affect pharmacokinetics?
Changes in absorption, ability of the meds to dissolve, blood flow, metabolism and excretion all slow down in the older adult
Discuss transcultural and genetic considerations regarding medication administration.