chapter 1. intro to drugs

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ICCT Colleges Foundation Inc.College of NursingSumulong Branch

Pharmacology LectureSY: 2011-2012 - 2nd year; 2nd sem

Prepared by: Ailyn Villegas-Banzuela RN

CHAPTER I.

A. Introduction to Nursing Pharmacology

I. Introduction to Drugs

The human body through a complicated series of chemical reactions and processes.

Pharmacology study of biological effects of chemicals

In the clinical practice, health care providers focus on how chemicals act on livingorganisms

The study of history, sources, physical and chemical properties of drugs

Is the science of drugs

Pharmacotherapeutics/clinical pharmacology the branch of pharmacology that uses drugs

to treat, prevent and diagnose disease

2 key concerns the drugs effects on the body

The bodys response to the drug

Adverse effects - is an expression that describes harm associated with the use of

given medications at a normal dosage.

(adverse drug reaction) ADRs may occur following a single dose or prolonged

administration of a drug or results from the combination of two or more drugs. The meaning of this expression differs from the meaning of "side effect", as this last

expression might also imply that the effects can be beneficial.

Drugs are chemicalsthat are introduced into the body to cause some sort of changes.

Can be helpful to both healthy and the sick

Drugs can come from plants, foods, salts, animals or synthetic sources

6 major USES of Drugs

1. The most common drug is used symptomatic treatment. Many drugs are used to relieve diseasesymptoms.

Ex: biogesic (paracetamol) fever, pain

Ponstan (Mefenamic acid) for pain

2. Preventive drugs help the body avoid disease

Ex: hepa vaccine

3. Diagnostic drugs help the physician determine whether a disease is present

Ex: radiopaque dye for IVP (procedure used to visualize abnormalities of theurinary system, includingthe kidneys, ureters, andbladder.)

4. Curative drugs to eliminate the disease
http://en.wikipedia.org/wiki/Medicationhttp://en.wikipedia.org/wiki/Drughttp://en.wikipedia.org/wiki/Side_effecthttp://en.wikipedia.org/wiki/Urinary_systemhttp://en.wikipedia.org/wiki/Urinary_systemhttp://en.wikipedia.org/wiki/Urinary_systemhttp://en.wikipedia.org/wiki/Kidneyhttp://en.wikipedia.org/wiki/Ureterhttp://en.wikipedia.org/wiki/Ureterhttp://en.wikipedia.org/wiki/Urinary_bladderhttp://en.wikipedia.org/wiki/Urinary_bladderhttp://en.wikipedia.org/wiki/Medicationhttp://en.wikipedia.org/wiki/Drughttp://en.wikipedia.org/wiki/Side_effecthttp://en.wikipedia.org/wiki/Urinary_systemhttp://en.wikipedia.org/wiki/Kidneyhttp://en.wikipedia.org/wiki/Ureterhttp://en.wikipedia.org/wiki/Urinary_bladder


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Ex: Ciprobay (ciprofloxacin) antibiotic for UTI

5. Health maintenance drugs help keep the body functioning normally

Ex: insulin

Multivitamins

Contraceptive drugs for prevention of pregnancy (Ex: trust pills (OCD)

The nurse is in a unique position regarding drug therapy because nursing responsibilities include the ff:

Administering drugs Assessing drug effects

Intervening to make the drug regimen more tolerable

Provided patient teaching about drugs and the drug regimen

Monitoring the overall patient care plan to prevent medication errors

Sources of Drugs

Drugs are available from varied sources both natural and synthetic.

1. Plants plant and plant parts have been used as medicines since prehistoric times

- Even today, plants are an important source of chemicals that are developed into drugs.Ex: digitalis serves as a powerful cardiac stimulant and a diuretic and used in

standardized form especially in the treatment of CHF

Plant Product

Ricinus communis Seed

Oil

Castor oil

Digitalis purpurea

(foxglove plant)

Leaves

Dried leaves

Digitalis leaf

2. Animals animal products are used to replace human chemicals that are not produce

because of disease or genetic problems

- Until recently, insulin for treating diabetes was obtained exclusively from the pancreas of

cows and pigs. Now, genetic engineering

3. Inorganic Compounds salts of various elements can have therapeutic effects in the human body.

Ex: aluminum, Fluoride

Iron, Gold

Element Therapeutic UseAluminum Antacid to decrease gastric acidity

Management of hyperphosphatemia

Prevention of the formation of phosphate urinary stones

Fluoride Prevention of dental carries

Prevention of osteoporosis

Gold Treatment of rheumatoid arthritis

Iron Treatment of iron deficiency anemia

Heart is unable to maintainadequate circulation of blood


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4. Synthetic sources technical advances allow scientists to alter a chemical with proven

therapeutic effectiveness to make it better.

Scientists use genetic engineering to alter bacteria to produce chemicals that are

therapeutic and effective

Ex: Demerol, ASA


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Drug Evaluation

After a chemical that might have therapeutic value is identified, it must undergo a series of

scientific tests to evaluate its actual therapeutic and toxic effects

The process is controlled by the FDA (food and Drug Administration)

Pre-clinical trials chemicals that may have therapeutic value are tested on laboratory animals for two

(2) main purposes1. To determine whether they have the presumed effects in living tissue

2. To evaluate any adverse effects

At the end of the pre-clinical trials, some chemicals are discarded for the following reasons:

The chemical lacks therapeutic activity when used with living animals

The chemical is too toxic to living animals to be worth the risk of developing into drugs

The chemical is highly teratogenic (causing adverse effects on fetus)

Some chemicals, however, are found to have therapeutic effects and reasonable safety margins. Such

chemicals will pass the pre-clinical trials and advance to phase I studies

Phase I studies use human volunteers to test the drugs

VOLUNTEERS

NOTE: Women are not good candidates for phase I studies because the chemicals may exertunknown and harmful effects on a womans ova, and too much risk is involved in taking adrug that might destroy or alter the ova. Men produce sperm daily, so there is lesspotential for complete destruction or alteration of sperm.

At the end of phase I studies, many chemicals are dropped from the process for the following reasons: They lack therapeutic effect in humans

They cause unacceptable adverse effects

They are highly teratogenic

They are too toxic

Some chemicals move to the next stage of testing despite undesirable effects.

Example :

Minoxidil (Loniten) was found to effectively treat malignant HPN but it is caused unusual hair

growth on the palms and other body areas (can proceed to the phase II studies)

Phase II Studies allow the investigators to try the drug in patients who have the disease that thedrug is meant to treat.

PATIENTS

Usually phase II studies are performed various sites across the country - Hospitals, clinics and doctors

offices and are monitored by the representatives of pharmaceuticals company studying the drug.

Are fully informed of possible risks and maybepaid for their participationUsually, the volunteers are healthy young men

Are told about possible benefits of the drugand are invited to participate in the study


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At the end of phase II studies a drug may be removed from further investigation for the following

reasons:

It is less effective than anticipated

It is too toxic when used with patients

It produces unacceptable adverse effects

A drug that continues to show promise as a therapeutic agent receives additional scrutiny in phase III

studies.

Phase III Studies involves use of the drug in a vast clinical market.

PRESCRIBER

NOTE: A drug that produces unacceptable adverse effects or unforeseen reactions isusually removed from further study by the drug company. In some cases theFDA may have to request that a drug be removed from the market.

FDA Approval drugs that finish phase III studies are evaluated by the FDA, only those drugs that

receive FDA committee approval may be market.

Continual Education (Phase IV) an approved drug is given a brand name (trade name) by the

pharmaceutical company that developed it.

Generic name of a drug is the original designation that the drug was given when the drug company

applied for the approval process.Chemical names are names that reflect the chemical structure of a drug.

After a drug is approved for marketing, it enters a phase of continual evaluation.

Some drugs cause unexpected effects that are not seen until the wide distribution occurs,

sometimes those effects are therapeutic

For example:

Patients taking the antiparkinsonism drug amantadine (symmetrel) were found to have

fewer cases of influenza than other patients, leading to the discovery that amantadine is

effective antiviral agent.

Legal Regulation of Drugs

The regulation of food and drugs in the Republic of the Philippines is enshrined in the 1987 Philippine

Constitution. Statutory laws are also in place providing legal basis for the creation of a regulatory

agency, the Bureau of Food and Drugs, mandated to ensure the safety, efficacy and good quality of all

food and drug products being made available to the general public.

The most important of these laws are Republic Act (RA) 3720 "Foods, Drugs, Medical Devices and

Cosmetics Act", RA 6675 "Generics Act", RA 8203 "Act Prohibiting Counterfeit Drugs", and RA 7394

"Consumers Act." Regulation is achieved through inspection and licensing of food and drug

Are informed of all the known reactions to thedrug and precaution required for its safe useObserve patients very closely, monitoring themfor any adverse effects.Sometimes the prescribers ask patients to keep

journals and record any symptoms theyexperience. Prescribers then evaluate thereported effects to determine whether they arecaused by disease or by the drug.


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establishments, registration and market monitoring of products, approval of product label prior to

marketing, and approval and monitoring of promotions and advertisements. International standards and

guidelines such as those recommended by the WHO, USP or BP, FAO and Codex Alimentarius are used as

a basis in the formulation and implementation of rules and regulations governing the manufacture,

importation, exportation, distribution, or sale of food and drugs. Compliance with the requirements of

good manufacturing practice is the basis criterion for licensing food and drug establishments, while

safety, efficacy and good quality are the criteria for registration of products.

Although cigarettes are not regarded as food or drug, the labeling and promotion of such is being

regulated by the Bureau because of the hazard posed to public health.

DANGEROUS DRUGS JURISDICTION: All matters directly and principally relating to illegal or prohibited drugs, controlledprecursors and essential chemicals, the production, manufacture, use and trafficking thereof, as well asthe rehabilitation and treatment of drug dependents.

Republic Act 9165 of 7 June 2002 institutes the Comprehensive Dangerous Drugs Act of 2002, repealing

Republic Act 6425, known as the Dangerous Drugs Act of 1972, as amended. Definition of terms;

unlawful acts and penalties; dangerous drug test and record requirements; participation of the family,students, teacher and school authorities in the enforcement of this Act; promotion of a National Drug-

Free workplace program with the participation of private and labor sectors and the Department of Labor

and Employment; participation of local government units; program for the treatment and rehabilitation

of drug dependents; Dangerous Drug Board and Philippine Drug Enforcement Agency; appropriations,

management of funds and annual report; jurisdiction over dangerous drugs cases; implementing rules and

regulations; final provisions. Amends Republic Act 7659. (102 sections; pp. 4325-4370)

Example of drug Monograph

GENERIC NAME

Pronunciation guide

BRAND NAME(S)

FDA pregnancycategory

Therapeutic Drug Drug Classes

Classess: Oxazolidinone

Action of Drug in Therapeutic actions

the body: Bacteriostatic and Bacteriocida; interferes with protein synthesis on the bacteria

ribosome: effective in vancomycin-resistant Enterococcus(VRE), staphylococcus,

and methicillin-resistant S. aureus (MRSA) and penicillin-resistant pneumococci

and S. aureus; is a reversible, non selective MAO inhibitor.

LINEZOLID

lin- AZE-oh- lid

Zyvox

Pregnancy Category C
http://www.congress.gov.ph/committees/search.php?congress=15&id=D502http://www.congress.gov.ph/committees/search.php?congress=15&id=D502


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Uses of the drug Indications

Evaluation points -Treatment of infection due to vancomycin-resistant Enterococcus faecnom

Resolution Or - Treatment of nosocomial and CAP due to S. aureus and penicillin susceptible

stabilization of Streptococcus pneumoniae

Those - Treatment of skin structure infections including those causes by methicillin-

Condition resistant S.aureus

- Treatment of diabetic foot ulcers without osteomyelitis

Conditions limiting Contraindications/cautions

Use of drug - contraindicated in presence of allergy to linezolid; pregnancy; lactationAssessment points phenylketonuria (oral form)

Hx of this condition, - uses of caution in the presence of bone marrow suppression, hepatic dysfuntion

Physical assessment HPN, hyperthyroidism, pheochromocytoma, carinoid syndrome.

Indicating these conditions

Forms and dosages Dosage

Available for use No dosage adjustment is needed if switching between oral and IV forms

Available forms: tablets-400, 600mg; oral suspension-100mg/5ml; IV solution

-2mg/mL

Recommended dose ADULT

Of drug for adults, - VRE, MRSA, pneumonia, complicated skin and skin structure infections,Pediatrics etc. Diabeticfoot ulcers: 600 mg IV or PO q12h for 10-28 days depending on infection

- Uncomplicated skin and skin structure infection: 400mg PO q12h for 10-14 days

PEDIATRIC: safely and efficacy not established

Action of the body on the Pharmacokinetics

drug-Assessment points Route Onset Peak

(hepatic and renal failure oral Rapid 1-2h

Cautions, and Metabolism:hepatic, T1/2: 5h

Contraindications Distribution:Crosses placenta; passes into breastmilk

Excretion:urine

Nursing actions for safe IV facts

And appropriate Preparation: Use premix solution available in 100, 200 and 300mL forms: store

Administration of the at room temperature, protect from light, leave overwrap in place until ready to

Drug in IV form use

Implementation-nursing Infusion: infuse over 30-120 min, switch to oral form as soon as appropriate.

Actions maybe infused into line using 5% dextrose injection, 0.9% NaCl, or Lactated Ringers

solution

Incompatibilities: do not introduce additives into this solution, do not mix in solution

do not mix in solution or at Y-connection with any other drugs. If other drugs are

being given through the same line, the line should be flushed before and after

linezolid administration.

Effects of drug in Adverse effects

The body therapeutic - CNS: headache, dizziness, insomnia, fatigue, somnolence, depression, nervousness

But can be expected - GI: Nausea, vomiting, dry mouth, diarrhea, anorexia, gastritis

Assessmentpoint - Hematologic: altered prothrombin time, thrombocytopenia

Baselines for these - Other: Fever, rash, sweating, photosensitivity, tendinitis

Systems Nursing Diagnosis

Potential alteration Resulting

from these Effects


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Evaluation Presence/absence

of these effects

Anticipated interactions Clinically important Interactions

Assessment points-hx - Drug-Drug: Risk for hypertension and related adverse effects of combined with

Of use of these agents, drugs containing pseudo ephedrine, SSRIs, MAOIs; uses caution and monitor

Physical response patient carefully if any of these combinations are used* Increased risk of bleeding

Evaluation changes from thrombocytopenia if combined with antiplatelet drugs (aspirin, NSAIDS),

Anticipated therapeutic monitor platelet counts carefullyresponse related to drug

interactions

FDA Pregnancy Categories

The FDA established five categories to indicate the potential for a systematically absorbed drug to

cause birth defects.

Category A Adequate studies in pregnant women have not demonstrated a risk to the

fetus in the first trimester of pregnancy, and there is no evidence of risk

in later trimestersCategory B Animal studies have not demonstrated a risk to the fetus but there are no

adequate studies in pregnant women, or animal studies have shown and

adverse effect, but adequate studies in pregnant women have not

demonstrated a risk to the fetus during the 1st trimester of pregnancy,

and there is no evidence of risk in later trimesters.

Category C Animal studies have shown an adverse effect on the fetus but there are no

adequate studies in humans; the benefits from the use of the drug in

pregnant women may be acceptable despite its potential risks, or there are

no animal reproduction studies and no adequate studies in humans.

Category D There is evidence of human fetal risk, but the potential benefits from theuse of the drug in pregnant women may be acceptable despite its potential

risks.

Category X Studies in animals or human demonstrate fetal abnormalities or adverse

reaction; reports indicative evidence of fetal risk. The risk use in pregnant

woman clearly outweighs any possible benefits.

Note: Regardless of the designated Pregnancy Category or presumed safety, no drug should be

administered during pregnancy unless it is clearly needed.

DEA Schedules of Controlled Substances

Drug Enforcement Agency DEA is the responsible in Controlled Substance act of 1970

regulations the manufacturing distribution and dispensing of drugs that are known to have

abuse potential.


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Controlled Substance Examples

Schedule I Controlled

Substances

Substances in this schedule have

a high potential for abuse, have

no currently accepted medical

use in treatment in the United

States, and there is a lack of

accepted safety for use of the

drug or other substance undermedical supervision.

Some examples of substances listed in

schedule I are: heroin, lysergic acid

diethylamide (LSD), marijuana (cannabis),

peyote, methaqualone, and 3,4-

methylenedioxymethamphetamine

(ecstasy).

Schedule II

Controlled Substances


a high potential for abuse

which may lead to severe

psychological or physical

dependence.

Examples of single entity schedule II

narcotics include morphine and opium.

Other schedule II narcotic substances

and their common name brand products

include: hydromorphone (Dilaudid),

methadone (Dolophine), meperidine

(Demerol), oxycodone (OxyContin),

and fentanyl (Sublimaze or

Duragesic).

Examples of schedule II stimulants include:amphetamine (Dexedrine, Adderall),

methamphetamine (Desoxyn), and

methylphenidate (Ritalin). Other

schedule II substances include: cocaine,

amobarbital, glutethimide, and

pentobarbital.

Schedule III



a potential for abuse less than

substances in schedules II and

abuse may lead to moderate orlow physical dependence or high

psychological dependence.

Examples of schedule III narcotics include

combination products containing less than

15 milligrams of hydrocodone per dosage

included are buprenorphine products(Suboxone and Subutex) used to

treat opioid addiction.

Examples of schedule III non-narcotics

include benzphetamine (Didrex),

phendimetrazine, ketamine, and anabolic

steroids such as oxandrolone

(Oxandrin).

Schedule IV



a low potential for abuse

relative to substances inschedule III.

An example of a schedule IV narcotic is

propoxyphene (Darvon and Darvocet-N

100).Other schedule IV substances include:

alprazolam (Xanax),clonazepam

(Klonopin), clorazepate (Tranxene),

diazepam (Valium), lorazepam

(Ativan), midazolam (Versed),

temazepam (Restoril), and triazolam

(Halcion).


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Schedule V Controlled

Substances


a low potential for abuse

relative to substances listed in

schedule IV and consist primarily

of preparations containing

limited quantities of certain

narcotics. These are generally

used for antitussive,

antidiarrheal, and analgesicpurposes.The purchaser must be at least18 years of age and mustfurnish suitable identification.

Examples include cough preparations

containing not more than 200 milligrams of

codeine per 100 milliliters or per 100 grams

(Robitussin AC and Phenergan with

Codeine).

Generic drugs are chemicals that are produced by companies that just manufacture drugs.

Note

The initial cost must

Be higher, but some

Prescribers, believeThat in the long run,

The cost to the

Patient will be less.

Orphan drugs are drugs that have been discovered but are not financially viable and therefore

have not been adopted by any drug company.

Maybe useful in treating a rare disease or they may have potentially dangerous drug

effect.

Over the Counter (OTC) are products that are available without prescription for self treatmentof variety complaints

because they dont have the research, the advertising or sometimes the quality control

departments, that pharmaceutical companies have, they can produce the genericdrugs so cheaply.

In the past, some quality-control problems were found with generic products.Ex: binders used in a generic drug might not be the same as those used in brand-

name product; as a result the, the way the body breaks down and uses the drugmay differ.

chapter 1. intro to drugs

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