Pharmacokinetics​- deals with the time course of​ drug concentration​s in the organisms

Pharmacodynamics​- deals w/ activity of a drug at the​ site​ of action

General Pharmacology​- tries to find general principles that apply to most drugs or classes of drugs
by examining numerous specific pharmacokinetic & pharmacodynamics.

Antigenic​ ​ ​ substance that can stimulate the production of antibodies a

● Aninfective​ ​used to prevent infection.
● Antibiotic​ ​inhibits the growth of microorganisms
● Antifungal​ ​aka “antimycotic medication” used to treat and prevent mycosis
such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections
such as cryptococcal meningitis,

Medical pharmacology​- science of substances used to prevent, diagnose, and treat disease

Clinical Pharmacology​- investigates new or established drugs in humans

EBP- evidenced based pratice

Toxicology​- deals w/ harmful properties of chemical compounds in humans & animals

Significance of Pharmacology in Nursing 

● Pharmacologic knowledge empowers nurses to function in the changing health care
environment.
● Successful, safe clinical practice is built on understanding the concepts & principles of
pharmacology
● Nurses are gaining more responsibility for appropriate use of drugs, accurate monitoring
& evaluation of drug effectiveness
 ● Enable the nurse to guide clients in safe medication administration
● A holistic nursing approach to care is crucial to the success of drug therapy initiation,
maintenance, and evaluation.

Introduction to Drugs 

Sources of Drugs 

● Drugs​ ​are ​derived from​ ​many sources, principally ​plants, animals, 

& minerals 
● Most ​modern drugs ​are​ synthetic chemical compounds 
manufactured in laboratories. 
*Synthetic- made by chemical synthesis, especially to imitate a natural product.

Semisynthetic drug​ - from natural drug to chemically treated , its like modified binago
● Made by synthesis from a naturally occurring material.
● Semi- half not pure
● Some are semi-synthetic drugs that are chemically altered or engineered; this group of
drugs are growing in importance as a source of drugs today.

Legal Regulation of Drugs

● Drug abuse and dependence​- ​were addressed in the comprehensive drug abuse prevention
and Control Act 1970, which regulated the distribution of narcotics and created the schedule of
controlled substances

● You need yellow prescription to get narcotics

 
● Comprehensive Dangerous Act no. 6425​ - ​was signed into law in the Philippines last ​June 7,
2002.

● Narcotics​- are antipsychotics, compulsant- irresistible, muscle relaxant

1906​- drugs should be free of ​adulterants - like water no effect sa gamot
1938​- ​testing for toxicity
1962​- proof of effectiveness - BFAD - bureau of food and drug administration
1970​ ​-​ controlled substance act - ​scheduled drugs
1997​ -​ f​ood and drug administration Modernization Act

Drug Standards 
Purity​- refers to uncontaminated state of the drug
● Additive are usually needed to facilitate the formulation of dosage forms

Potency​ - generally depends on the concentration of ​active drug​ in the preparation -nakakalasing
na gamot

Bioavailability​ - the ​degree to w/c a drug can be absorbed by the body ​and transported to its site
of action

Efficacy​- refers to the ability of a drug use in treatment of illness or disease to be effective

Safety/ Toxicity:

1. All chemicals are toxic to some degree

2. The safety of a drug is measured by the incidence and severity of adverse
reactions
*incidence- frequency of disease

3. Safety is determined by the ​degree between therapeutic and toxic dosages

(Therapeutic Index)
4. Complete safety can not be determined regardless of testing​ before release of a
drug
 3 Drug Preparations 
Chemical name 
● The chemical structure of the drug 
Ex. N-acetyl-p-aminophenol

generic name 
● Name selected by the original manufacturer of the drug based on the 
chemical structure 
● Simpler, ​*first letter not capitalized, ALL LOWER CASE! 
Ex. paracetamol acetaminophen

Brand name / proprietary name (​AKA “​trademark​”​) 

● Followed by the symbol 
● Indicates that the name is registered and that its use is restricted to the 
owner of the drug, who is usually the manufacturer 

Ex. Tylenol

Drug Families/ Drug Classification

 ● Refers to the taxonomies of drugs related to either mechanism of action or
therapeutic indications

Ex. antibiotics, anticholinergic -​ i​nhibit parasympathetic nerve impulses​, analgesic -​ ​relieve

pain.

May be classified according to:

1. What body system they affect Ex. drugs affecting the cardiovascular system
2. Therapeutic use/ clinical indications Ex. antacids- ​neutralizes stomach acidity,​ ​relieve upset
stomach ​, diuretics -​ aka “water pills”, it i​ncreases production of urine.
3. Physiologic or Drug action Ex. anticholinergic, calcium- channel blockers - ​disrupt the
movement of calcium through calcium channels.

🌸Classification of Drugs🌸
Prescription Drugs ​ - ​ yellow precription drugs haha

● Those that may not be used except after professional consultation.

Ex. ​hormones, antibiotics 
● Those that affect central nervous system & may cause dependence
Ex. a​mphetamine​- a cns stimulant , ​barbiturates​ - ​reduce the activity of nerves
causing muscle relaxation

Non- Prescription Drugs / Proprietary Drugs

 ● Those that may be widely purchased for self-treatment of symptoms of minor-limiting
diseases

Over- the- Counter- Drugs

● Those available in pharmacies, used in advice of health professional for control of

minor self-limiting disease
Ex​. Mefenamic acid​ - for menstrual /tooth pain

Illegal Drugs/ Recreational Drugs

● Drugs or chemical substances used for non-therapeutic purposes

● Obtained illegally or have not received approval for use by the FDA.

Principles of Drug action and Drug Interaction 

Pharmacodynamics​ - deals with the interactions between the chemical

components of living systems and the foreign chemicals including drugs that enter
those systems.

2 effects of Pharmacodynamics:
● Primary effect - give desirable effect
● Secondary effect- give either desirable/undesirable effect like side effects
Receptor sites
a. Reacts w/ certain chemicals to cause an effect within the cell
b. The nearby enzymes break down the reacting chemicals and open up the receptor site for
further stimulation
c. Acts as key and lock ​-either activate or block (inhibit receptors)

4 Receptor Families: 
1. Cell membrane embedded enzymes’ ​Na-sodium outside cell 
2. Ligand-gated ion channels ​K- potassium inside cell 
 3. G Protein-coupled receptor system 
4. Transcription factors​ -
​ ​ ​the DNA inside nucleus w/c regulates protein synthesis

 
​2 Types of Drug Interaction ‘   
 
● Agonist - interact directly w/ receptor sites to cause the same 
activity that natural chemicals would cause at the site 
 
*nagactivate sya  
Ex. Insulin Low glucose = stimulate Insulin  
 
● Antagonist - drugs that block the actions of endogenous regulatory 
 
*block 

🌼Non-​specific​ ​Drug Effect ​- ​a drug that stimulates or blocks the cholinergic

receptors affects all the anatomic sites

Cholinergic Receptors divided into 6:

1. Bladder
2. Heart
3. Blood vessel
4. Stomach
5. Bronchi
6. Eyes
 🌼 ​- ​drugs that affects multiple receptors
 
Non-​selective​ Drug Effect​

Non-​selective​ Drug Effect : 

● Alpha 1 
● Beta 1 
● Beta 2  

Pharmacokinetics​ ​- how the body acts on the drug ​*movement of drug on the body daw

Drug Action - drugs usually work or act in one of the 4 ways:

a. To replace or act as substitutes for missing chemicals
b. Increase or stimulate certain cellular activities
c. To depress or slow cellular activities
d. Interfere w/ the functioning of foreign cells; such as invading microorganisms or
neoplasm- is parang maga

5 ​Process of ​Pharmacokinetics 

1. Absorption​- refers to what happens to a drug from the time it is introduced to the body
until it reaches the circulating fluids and tissues.

Three process of Absorption:

➢ Passive Transport -​ d​iffusion and facilitated diffusion
➢ Active Transport -​ requires a carrier to move the drug against a concentration gradient
➢ Pinocytosis -​ cells carry drug across their membrane by engulfing the drug in a vesicle

*Bioavailability- percentage of the administered drug dose that reaches the sytemic
circulation
 Factors affecting bioavailability:
a. Drug form
b. Route of administration
c. GI mucosa, and motility
d. Food and other drugs
e. Changes in liver metabolism

2. Under absorption is​Dissolution​- a drug in solid must disintegrate in small particles

and combine with a liquid.
3. Distribution​- movement of drug to the body’s tissue

Factors affecting:
● Rate of blood flow
● Drugs affinity to tissues affinity- means similarity
● Protein binding - drugs can be bind w/ proteins

Impedes drug’s ability to reach sites of action, metabolism, or excretion

1. Blood brain barrier
2. Placenta/ breastfeeding

4. Metabolism​- biotransformation enzymatic alteration of drug structure

● Liver enzyme system-​ ​most important daw

Sites of biotransformation:
a. Liver
b. GI
c. Circulating chemicals

Consequences of ​ ​Metabolism​:
● Accelerated renal excretion -​ kidney cannot excrete highly lipid soluble
● Drug inactivation
● Increase therapeutic action
● Increased/decreased toxicity
 Considerations in ​Metabolism​:
● Age
● Induction of drug metabolizing enzymes
● First-pass effect
● Nutritional status
● Competition between drugs

5.​ ​Excretion​- removal of drug from the body

Can occur thru:

a. Skin
b. Saliva
c. Lungs
d. Bile
e. Feces
f. kidneys

Adverse Drug Reactions 

❏ Side effect
❏ Toxicity

🥀- ​
❏ Allergic reaction

👱 -​
❏ Idiosyncratic effect in minimum dose it will react

❏ Iatrogenic disease ex. Continuous therapy like radiation/chemotherapy then patient lose
hair

❏ Physical dependence
❏ Carcinogenic effect ​ex. Leads to cancer like taking pills
❏ Cumulative reactions -​ either u will have problem in kidney or liver
❏ Tolerance and Dependence
❏ Clinically Desirable Interactions​ ex. Glutathione