Student Core Concepts

Basic Pharmacology Concepts: 

Science 355 Basic Pharmacology Concepts

Pharmacology Basic terms: 

Pharmacology Basic terms Drug: any chemical that can affect living processes Pharmacology/Clinical Pharmacology: the study of drugs and their interactions with living systems (clinical = in humans) Therapeutic: use of drugs to diagnose, prevent or treat disease

The 3 most important characteristics of any drug: 

The 3 most important characteristics of any drug Effectiveness: the most important property a drug can have Safety: defined as cannot produce harmful effects. There is no such thing as a safe drug. Selectivity: does not produce side effects. There is no such thing as a selective drug . All medications cause side effects.

Beyond the 6 Rights: 

Beyond the 6 Rights You are the patient’s last line of defense against medication errors.

The importance of the nursing process: 

The importance of the nursing process Linking our assessments with our knowledge of medications can significantly prevent patient injury. Evaluating drug response one of the most important and common things that we do. Implementing PRN medications… Patient Education

How new drugs are developed: 

How new drugs are developed Randomized double blinded controlled trials (RCTs) using placebo is the gold standard Preclinical testing Phase I testing Phase II and III testing Phase IV surveillance

Drug Names: 

Drug Names The three types of drug names Chemical (nurses rarely use) Generic – preferred choice – each drug has only one generic name Trade (proprietary or brand) – developed by drug companies

Over the counter (OTC) drugs: 

Over the counter (OTC) drugs Can be purchased without a prescription

Pharmacokinetics: 

Pharmacokinetics Pharmakon (poison) and kinesis (motion) = study of drug movement throughout the body. 4 phases of pharmacokinetics: Absorption Distribution Metabolism Excretion

Absorption: 

Absorption Movement of a drug from where it’s administered into the blood. Enteral versus Parenteral Enteral or PO (per os …. By way of the mouth) From GI tract to liver to inferior vena cava to general circulation Hepatic metabolism is variable…. Safer than injection Parenteral Rapid onset (which is irreversible) Complete absorption Can be dangerous

Distribution: 

Distribution Movement of drugs throughout the body Determined by blood flow Blood brain barrier: A safety mechanism that prevents passage of many drugs into the brain. Protein (albumin) binding: keeps drugs in the bloodstream

Metabolism: 

Metabolism Enzymatic alteration of drug structure Most happens in the liver The cytochrome P450 system – important component of some adverse drug effects First pass effect – occurs with some drugs when the liver inactivates the drug

Excretion: 

Excretion Removal of drugs from the body The kidneys remove most drugs from the body

Pharmacodymics: 

Pharmacodymics What drugs do the body and how they do it Maximal Efficacy: largest effect that a drug can produce Agonists: molecules that activate receptors Antagonists: molecules that prevent receptor activation

Drug Interactions: 

Drug Interactions Drug-Drug interactions Additive effects Interference Drug-Food interactions Food may slow the absorption of drugs Some foods have substances that react with certain drugs Example MAO and tyramine rich foods Coumadin and Vitamin K rich foods Tetracycline and dairy products

Slide 18: 

Grapefruit Juice effect

Adverse drug reactions: 

Adverse drug reactions Types of Adverse Drug reactions Side effects (nearly unavoidable) Toxicity (caused by excessive dosing) Allergic reaction Idiosyncratic effect (uncommon drug response) Iatrogenic disease (disease produced by drugs) Carcinogenic effect (causes cancer) Teratogenic effect (can cause birth defects) Organ specific toxicity Hepatoxicity QT interval drugs

Medication errors: 

Medication errors Human factors Performance deficits (30%) Knowledge deficits (14%) Miscalculation of dosage (13%) Communication mistakes (16% of all errors) Name confusion (15%)

Individual Variation: 

Individual Variation Body weight Kidney disease Liver disease Tolerance Genetics Gender Race Compliance Drug interactions Diet

PharmacogenEtics: 

PharmacogenEtics Study of how one’s genetic make-up affects drug pharmacokinetics and pharmacodynamics Genes determine the types and amounts of proteins produced by the body

Teratogenesis: 

Teratogenesis Highly dependent upon when drug is given FDA pregnancy risk categories: A, B, C, D & X Breast feeding

Pediatrics: 

Pediatrics Huge gaps in our knowledge Pediatric patients are not little adults – changes in: Absorption Distribution Excretion

Geriatrics: 

Geriatrics Major issues: Altered pharmacokinetics (organ system degeneration) Multiple, severe illnesses Polypharmacy Poor adherence