Pharmacology Basics

• Drugs
• Chemicals introduced into the body to cause a change.
• Affect physiological processes in living organisms.
• Medicine
• Substances used to treat, control, or cure a condition.
• All medicines are drugs, but not all drugs are medicines.
• Therapeutic Drug
• Used to cure, prevent, or treat.
• Has components that determine its effectiveness and safety, and may have minor side effects.
• Pharmacology
• Deals with drugs, their uses, and biological effects.
• The study of drugs and their interactions within living systems.
• Includes adverse drug reactions.
• Derived from Greek, with "pharmacon" meaning drug and "logos" meaning study.
• Oswald Schmiedeberg is considered the "father of pharmacology".

Pharmaceutics

• Concerned with how drugs are formulated to influence pharmacokinetic and pharmacodynamic activities.
• Dosage form design can affect dissolution.
• Takes a new chemical entity and turns it into a safe and effective medication.

Pharmacokinetics

• Studies what the body does to the drug.
• Addresses how a drug moves through the body and is eliminated.
• Includes processes of absorption, distribution, metabolism, and excretion.
• "Kinesis" is Greek for movement.
• Liberation is the first step, where medication enters the body and releases the active ingredient.

Pharmacodynamics

• The study of what the drug does to the body.
• Deals with the mechanism of drug actions in living tissues.
• Studies how drugs produce their effects (biochemical and physical).

Pharmacotherapeutics

• It covers the clinical uses of drugs to prevent and treat diseases.
• Empirical therapeutics: Effective, but mechanism of action is unknown.
• Rational therapeutics: Uses specific evidence for drug action mechanisms.
• Applies pharmacological information with disease knowledge for prevention, mitigation, or cure.

Posology

• Deals with the doses of drugs needed for desired pharmacological actions.

Pharmacogenetics

• Studies inherited characteristic patterns of interaction between chemicals (drugs) and organisms.
• Involves distinguishing heritable patterns from non-heritable ones.
• Highlights similarities and differences in pharmacodynamic and pharmacokinetic mechanisms.

Chronopharmacology

• Examines the relationship between administration time and drug effects.
• Seeks to understand how drug effects vary with biological timing and periodicities.
• Aims to improve understanding of predictable changes in desired effects and tolerance of medication.

Pharmacy

• The science of identification, compounding, and dispensing of drugs.
• Includes collection, isolation, purification, synthesis, and standardization of medical substances.

Toxicology

• The study of biologic toxins.
• Addresses the sources, tests, and antidotes of poisons, and their harmful effects.
• Covers poisons, their sources, chemical composition, action, tests, and antidotes.

Pharmacognosy

• The study of natural (plant and animal) drug sources.

Sources of Drugs (Natural)

• Plants: Common source; includes leaves, roots, bark, sap, seeds, bulbs, fruits, blossoms, extracts.
• Alkaloids: Active components; alkaline, bitter; form salts with acids, e.g., Caffeine, Nicotine, Atropine.
• Glycosides: Digitalis from wildflower foxglove; lanoxin, digoxin.
• Resins: Soluble in alcohol; colonic irritants in cascara.
• Oils: Thick, greasy liquids; peppermint, spearmint, juniper, oil of wintergreen, castor oil, olive oil.
• Animals: Body fluids, glands; hormones like insulin; enzymes; vaccines.
• Minerals: Provide inorganic materials; acids, bases, or salts; e.g., FeSO4, MgSO4, dilute HCl, Calcium, aluminum, fluoride, iron, gold, potassium.

Sources of Drugs (Synthetic)

• More potent, stable, less toxic, safer; genetically engineered.
• Chemical (Propranolol).
• Biological (Penicillin).
• Biotechnology (Human Insulin).
• Steroids (for arthritis).
• Sulfonamides/chemotherapeutic agents (synthesized).
• Recombinant DNA Technology/Genetic Engineering:
• Insertion of Human or Human Modified Pro-insulin Gene into E. Coli or yeast. New technique for preparing drugs.
• Mass production.
• Cost effective.
• Fewer immunological reactions.

Philippine Laws Related to Drugs

• RA 9165 - Comprehensive Dangerous Drugs Act Of 2002: Deals with importation of dangerous drugs, offenses, and penalties.
• RA 6675 - Generics Act of 1988: Use of generic terminology and ensures supply generic names the lowest possible cost.
• RA 6425 - Dangerous Drugs Act of 1972: Focuses on prohibited and restricted drugs.
• RA 953 - Narcotics Drug Law: Imposes taxes on those dealing with opium, marijuana, opium poppies, coca leaves, or synthetic drugs.
• RA 9502 Universally Accessible Cheaper and Quality Medicines Act of 2008 amends: RA 8293 Intellectual Property Code, RA 6675 Generics Act of 1988, RA 10918 - Philippine Pharmacy Law of 2016.
• RA 10918 - The Philippine Pharmacy Law of 2016: Regulates pharmacy practice in the Philippines and expands scope to include immunization.

Ways of Standardizing Drugs

• Approval of new drugs through US FDA and FDA-Philippines (formerly BFAD).

Creating Drugs

• Respect for Person (informed consent), Beneficence (risk-benefit ratio), and Justice are key ethical considerations.

Drug Standards

• Standardize drug names/formulas.
• Provide standards for the identity, purity and qualify of drugs.
• Ensure uniformity.

References on Drug Standards

• Philippine Index of Medical Specialties (PIMS)
• Medimedia Index of Medical Specialties (MIMS)
• United States Pharmacopeia (USP)

The Philippine National Drug Formulary (PNDF)

• An integral component of the Philippine Medicines Policy.
• Aims to provide essential, quality, safe, and affordable drugs.

Essential Drugs List (EDL)

• For primary medical care based on PNDF.
• Contains a list of drugs useful in meeting the needs of the majority.

Research and Pharmacology

• This includes:Independent, dependent variable, extraneous variable (age, sex, weight, disease state), experimental and control groups, placebo.

Drug Nomenclature

• Chemical Name: Early stage name (chemical structure).
• Generic Name: Nonproprietary/common name.
• Trade Name: Brand/proprietary name.

3 Phases of Drug Action

• Pharmaceutics (Dissolution): Drug dissolves for absorption.
• Not needed in parenteral administration.
• Enhance drug dissolution( ex. potassium (K), sodium (Na)
• Disintegration and Dissolution.
• Rate limiting - time it takes drug to disintegrate.
• Excipients - affect dissolution.

Factors Affecting Dissolution

• Form of drug: Liquids absorb faster.
• Gastric pH: Acid promotes disintegration.
• Age: pH affects absorption.
• Enteric coated drugs: Resist gastric acid.
• Presence of food: Can interfere.

Pharmacokinetics Description

• How the body acts on the drug through absorption, distribution, metabolism, and excretion.
• Considers onset, peak concentration, and duration.
• Includes the concept of drug half-life.

Pharmacodynamics Description

• How the drug affects the body.
• The biochemical/physiological effects and mechanism of action.

Main Mechanisms of Action

• Alteration in cellular environment: Physical and chemical changes.
• Alteration in cellular function: Affecting cell activities.

Pharmacokinetic Processes

• Absorption: Drug passage into the bloodstream.
• Rate: Rate and extent of absorption is determined by:
• drugs ability to leave its site of administration
• Drugs site-to-pass across the body's membrane
• The area of absorption is usually the small intestines.
• Bioavailability: Rate and extent of absorption (0-100%).
• Bioequivalence: Same bioavailability.

3 Processes of Absorption

• Passive absorption (diffusion): High to low concentration.
• Active transport: Uses energy via a carrier.
• Pinocytosis: Engulfs drug in the membrane.

Administration and Absorption

• Oral: Most common route, non-invasive and practical BUT is affected by the presence or absence of stomach acid.
• Intravenous: Drugs directly enter bloodstream, but may cause toxic effects.
• Intramuscular: Absorbed into capillaries, faster in men.
• Subcutaneous: Absorbed rapidly.
• Rectal: Absorbed by perfusion.
• Respiratory: Targets the lungs.
• Buccal/sublingual: Rapid absorption, bypasses GI tract.
• Topical: For superficial use only.
• Special areas/infusions: Epidural, intrapleural, intraperitoneal, intraosseous.

Factors Affecting Drug Absorption

• Route of administration.
• Blood flow.
• Drug solubility.
• First-pass effect.
• Lidocaine and NTG drug examples.

Other Factors Affecting Drug Absorption

• Drug solubility: Lipid soluble is best.
• Local site condition.
• Pain and stress.
• Drug concentration formulation.
• Circulation.
• Exercise decreases GI absorption
• Heat increases blood flow and distribution.
• Fluids.
• Absorptive surface.
• Acidity.
• Gl Motility.
• Binding (protein).

What affects bioavailability?:

• Drug form.
• Route of administration.
• GI mucosa and motility.
• Food and drugs can affect bioavailability.
• Liver function.
• Low protein-bound drugs.

What affects drug distribution?:

• Size of the organ.
• Blood flow to body tissues (heart, liver, kidneys, etc.).
• Drug's lipid solubility and ionization.
• Perfusion of reactive tissue.
• Protein binding.

Metabolism (Biotransformation) Info

• Process of changing the drug in the body. (Liver)
• Drugs are converted by the liver. (Enzymes)
• Makes drugs more water soluable so they can be excreted more easily.

Primary Sites of Metabolism

• Liver= main organ. First pass metabolism
• Through Drug metabolizing enzymes.
• Plasma
• Lungs
• Kidneys
• Membranes of the intestines
• Hepatic first pass- amount of drug goes to liver via portal vein, gets metabolized to innactive form, and decreases active drugs, Increase recomended dose

Factors Afftecting Drug Metabolism

• Age
• Nutrition
• Insuficient hormones

Other Factors of Drug Metabolism

• Physiology
• Area of absorbing surface to which a drug is exposed
• Types of transport
• Routes of administration
• Excretion (Elimination)- Process of removing drug and its metabolites.
• Skin, Salvia, lungs, Bile, Feces, Urine, Kidneys

Factors Affecting Drug Excretion

• Renal excretion
• Drugs
• Blood concentraion levels
• Elimination half-life - time it takes for ½ of the drug to be excreated.

More on Half-Life

• Short half-life= frequent
• Long half-life = Less frequent
• Time it takes 5-6 half lives to eliminate 98% Difficulty excreting, increases half-life risks toxicity (digoxin= long half-life- only takes once daily)

Key Half-Life Drugs

• Aspirin (Needs frequent dosing)
• Digoxin (Can only dose once daily)

Therapeutic Drug Levels

• Know the range of different therapeutic durgs. Knowing half-life of to determine the time it takes to for a drug to reach steady state of serum concentraion Loading dose or larger dose (intended for thearapeutic effect)

Drug Interaction

Drug interaction- effects are altered by other medications or food. Synergistic or potentiation increases the drug's effect. Trough Drug Level- lowest plasma concntation

• Rate of elimination. Peak Drug level- Highest concentration
• Rate of absorption.
• Therapeutic effects are desired and intentional affects.
• Intended therapeutic action (benefitial), Unintended (predictable or adverse reactions)

Antagonist and Agonist

• Antagonist has a affinity for a receptor, displays of activity.
• Agonist drugs the produce a response, and are a antagonist that blocks activity.
• Occupiys receptors sites for Acetylcholine, for preventing nerve stimulation to create paraylis.

Other Drug Info

• Therapeutic index effects altered by their interaction with other medecation.
• Tachyphylaxis - less effective

Dose Response Described

• Potency - Amount needed to elicit a specific response
• Receptor (Drugs that act on specific areas of the cell membrane)
• Drug actions areas on cell embranes
• Drug binding sites (protien etc)

4 Phases of Affecting Drug Activity

• 1st phase Pharmaceutics phase
• 2nd Phase Pharmacokinetic
• 3rd Phaser Pharamacodynamics Interation

Nursing Actions

• General rules with drug adminerstrations and checking doctor's orders.
• Medication interactions within the body.

Allergic Reactions/ Side Effects

• Alergic Reaction: when the drug is sensitive to the medical.
• S/S may lead to anaphylactic shock or angoideame
• Anaphylaxis :bronchospsms, despena, wheezing
• Treatmtn would be epinephrine .
• toxic to the liver and kidneys
• Causes a toxic state within the body

Other Side Effects

• Neurotoxic and ototoxic
• Auditory vision disturbances.
• Always asses baseline and follow through vision change.
• Photosensativity reactions skin can blister and burn.
• Hyperglycemia can affect and lower glucose levels

Drug Interaction

• Hyopkalcemia (drug affects kidney)
• Other Drug Interactions

Pregnancy Category

• Category can vary on drugs , A's are okay, X's you should hold.
• Drug names, chemicla or gerneric.
• Brand and trade

Nursing Process

• ADPIE
• What the steps

Assesment and Planning

• Subject and objectives ways to get informations
• How to care plan after knowing information

Action steps

• Steps to drug admin
• right the way , meds
• What to follow for the right protocols
• Documentation
• Verbal order and telephone orider
• Medcal errors.
• What is SAM.
• Factores affecthing responses

Safety Actions and Drug Admin

• Always do the 10 rights of adminstration!
• What to remember the safety when using patients.
• What the DO's and Don't's in doing a treatment.
• Review of the drug and methods of dose
• Always ask if needs, if not dont admin.

Key Reminders

• Aseptic teachnique if injectables
• Do know similar drug names that it will happen with medication, to be careful
• If a patietn can't read, dont assume and always ask for assistant to help
• Dose needs to be given with the prescripitin what is needed
• Keep calm in cases of emmergency.

Considerations Drug Administrations

If giving drug be sure the route to give. Always tell the client that is giving and reason for it. Right cleint always check armband and client Always check the orders for correct dose and label, make sure 3 times

Drug Dosage

If in dout re-do correct the dosage Never admister if others person already prepare

Drug Administration

Keep the safety in mind. Always do the rights Make sure the client not allergic to the medications