Pharm Exam #1

Pharmacology

the study of drugs and their interactions with living systems

Medication

A chemical substance that is used to treat or prevent disease or relieve pain.

Local effects of medications

act mainly at the site of application

Systemic effects of medications

taken into the body, circulated via the bloodstream to sites of action, and eventually eliminated from the body

Name drug sources

Plants, animals, minerals, synthetic compounds

How are drugs classified?

According to their effects on particular body systems, their therapeutic uses, and their chemical characteristics.

What are drug prototypes?

Individual drugs that present a group of drugs

What is an example of a drug prototype?

Morphine represents analgesics

How many names can a drug have?

3

What are the names of a drug?

Generic name, trade name, and chemical name

What is the risk of using different drug names for the same medication?

It increases confusion and the risk of misuse of a drug

How can drugs be accessed?

By prescription or over the counter

Prescription drugs

Medicines that cannot be used without the written approval of a licensed physician

Over the counter drugs

Drugs available to consumers without a prescription. Also called nonprescription drugs

Comprehensive Drug Abuse Prevention and Control Act

Gives a level of control over high abuse medications

Controlled Substances Act

The federal law giving authority to the Drug Enforcement Administration to regulate the sale and use of drugs.

Categories of Controlled Substances

Schedule I
Schedule II
Schedule III
Schedule IV
Schedule V

Schedule I

This type of drug has no accepted medical use in the United States.

Examples of schedule I drugs

heroie, marijuana, ecstasy

Schedule II drugs

a type of drug with medicinal uses that is highly addictive and only available with a prescription

Examples of schedule II drugs

oxycodone, fentanyl, morphine

Schedule III drugs

a type of drug with medicinal uses that is moderately to highly addictive and only available with a prescription

Examples of schedule III drugs

ketamine, testosterone, anabolic steroids

Schedule IV drugs

a type of drug with medicinal uses that is moderately addictive and only available with a prescription

Examples of schedule IV drugs

lorazepam, tramadol, diazepam

Schedule V drugs

a type of drug with medicinal uses that is not very addictive and only available with a prescription

Examples of schedule V drugs

Lomotil, Robitussin AC

Who is responsible for approving new drugs in the US?

FDA

Beers Criteria

A list of medications that are generally considered inappropriate when given to elderly people

What are some sources for drug information?

Textbooks, internet sites, drug reference books, and journals

Authoritative sources

sources that use factually verifiable observations and data to provide rigorous conclusions that will not collapse under scrutiny

Pharmacokinetics

The process by which drugs are absorbed, distributed within the body, metabolized, and excreted.

ADME

absorption, distribution, metabolism, excretion

Rights of Medication Administration

Right drug
Right dosage
Right patient
Right route
Right time
Right reason
Right evaluation
Right documentation
Right to education
Right to refuse

Where are drug metabolizing enzymes located?

Kidneys, liver, RBCs, plasma, lungs, GI mucosa

Enzyme induction causes

Increased action (higher dosage)

Enzyme inhibition causes

Decreased action (lower dosage)

Serum drug level

Lab measurement of the amount of a drug in the blood at a particular time

minimum effective concentration

amount of drug required to produce a therapeutic effect

Toxic concentration

level of drug that results in serious adverse effects

Toxic concentration is caused by

A single large dose, many small doses given too frequently, and slow metabolism

receptor theory of drug action

Most drugs exert their effects by chemically binding with receptor cells through
-Activation, inactivation, or alteration of intracellular enzymes
-Changes in the permeability of cell membranes to one or more ions
-Modification of the synthesis, release, or inactivation of neurohormones

Agonists

drugs that increase the action of a neurotransmitter

Antagonists

drugs that block the function of a neurotransmitter

Nonreceptor drug examples

antacids, osmotic diuretics, anticancer drugs, metal chelating agents

Nonreceptor drugs

Drugs that do not act on receptor sites

Receptor drugs

Have to bind to receptor sites to produce a reaction

How does dosage effect drug reaction?

Frequency, number of doses, and size of dosage

How does the route of administration effect drug reaction?

Influences absorption and distribution

Drug to diet interactions

When elements of ingested nutrients interact with a drug and this affects the disposition of the drug

Drug to drug interactions

when the effect of a medication is changed, enhanced, or diminished when taken with another drug, including herbal substances

Additive effects

Drug interactions in which the effect of a combination of two or more drugs with similar actions is equivalent to the sum of the individual effects of the same drugs given alone.

Synergism

combination of two drugs causes an effect that is greater than the sum of the individual effects of each drug alone

interference drug reaction

1 drug inhibits the metabolism or excretion of a 2nd drug, causes increased activity of the 2nd drug

Displacement drug reaction

displacement of 1 drug by a 2nd, increasing activity of the 1st

Pharmacogenomics

the study of how genetic inheritance affects the body's response to drugs

Pharmacogenetics

the study of how genetic variation affects an individual's response to drugs

Drug half life

the time required for the amount of drug in the body to decrease by 50%

t = 1/2

Equation for drug half life

What schedule of drugs is the least controlled?

Schedule V - least addictive

Which schedule of drugs is the most controlled?

Schedule I - most addictive

How do patients stretch their medications?

Patients will attempt to skip medications, cut a dosage in half, or use other family members' medications

Polypharmacy

The use of many different drugs concurrently in treating a patient, who often has several health problems.

Why might a patient try to stretch their drug supply?

They cannot afford the medication

Black Box Warning

A type of warning that appears in a drug's prescribing information and is required by the U.S. Food and Drug Administration (FDA) to alert prescribers of serious adverse events that have occurred with the given drug.

Examples of black box warning medications

Antidepressants

Therapeutic Index

the ratio between the toxic and therapeutic concentrations of a drug

Routes of administration of drugs

intramuscular, oral, subcutaneous, sublingual, intravenous, topical

"Do Not Use" abbreviation list

QD/QOD (for daily/every other day)
U for unit
IU for international unit
MS/MSO4/MgSO4 (for morphine/magnesium sulfate)
Trailing zeros (e.g. 2.0 mg) following whole numbers
Naked decimal points (e.g. .5 mg) preceding doses less than zero
Available on ISMP or JACHO website

Needle gauge

measurement of the diameter of a needle (lumen)

A larger needle has a

smaller lumen

A smaller needle has a

larger lumen

Needle size depends on

patient size and weight, route of administration, and blood viscosity

What can affect drug absorption?

Blood flow, pain, stress, hunger, fasting, food, pH, dosage form and route of administration

Which oral dosage form of medication is faster in its absorption?

Solutions or liquid are absorbed faster than tablets.

How are dosages determined for pediatric patients?

Peds doses are milligram per kilogram based upon the patient's weight

What does it mean if a drug is protein bound?

Drugs that are protein bound cannot be distrusted through the body, only free drugs can cause action

Absorption changes in older adults

Lower acidity in stomach, decreased blood flow in intestines; not clinically significant

Distribution changes in older adults

Body water and lean body mass decreases, body fat % increases and causes high protein binding; lowers effectiveness of drug

Metabolism changes in older adults

Decline in metabolic capacity, decreased liver mass and hepatic blood flow

Excretion changes in older adults

Decreased renal blood flow, GFR is established

Examples of authoritative sources

American hospital formulary service

What patient age range is more susceptible to toxic concentration due to incorrect medication dosage?

Pediatric patients

What needs to be included on an Rx?

Patient name, name of medication (brand or generic), dosage, route, and frequency of administration, date, time, and signature or prescriber

What is the preferred method of ordering medication?

Typed into a computer

What must nurses know before giving a new drug?

Side effects, target patient age, preferred method of administration, and main use (for which ailment)