📚 PHARMACOLOGY STUDY GUIDE
For Nursing Students
Based on “Focus on Nursing Pharmacology” by Amy M. Karch and the Nursing
Drug Handbook
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🧠 1. Introduction to Pharmacology
Definition:
Pharmacology is the branch of science that deals with the study of drugs,
their sources, properties, effects, and uses in treating diseases.
Importance in Nursing:
Ensuring safe medication administration
Performing accurate dosage calculations
Monitoring for therapeutic and adverse effects
Providing patient education
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🔬 2. Pharmacokinetics
“What the body does to the drug”
✴️Key Processes (ADME):
Process Description
Absorption How a drug moves from the site of administration into the blood-
stream
Distribution How the drug spreads through body fluids and tissues
Metabolism (Biotransformation) How the body chemically changes the drug,
mainly in the liver (via cytochrome P450 enzymes)
Excretion How the drug or its metabolites are eliminated, primarily through
the kidneys, but also through lungs, sweat, bile, and feces
❗Factors Affecting Pharmacokinetics:
Route of administration
Blood flow to tissues
Liver/kidney function
Age, weight, and body composition
Drug solubility and protein binding
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⚙️3. Pharmacodynamics
“What the drug does to the body”
Key Concepts:
Mechanism of Action: How the drug produces its effect (e.g., binding to recep-
tors, enzyme inhibition).
Drug-Receptor Interaction:
Agonist – Activates a receptor to produce a response.
Antagonist – Blocks the receptor to prevent a response.
Therapeutic Index (TI): Margin between the therapeutic and toxic dose.
Onset: Time it takes to start working.
Peak: Maximum drug effect.
Duration: How long the effect lasts.
Half-life (t½): Time for half the drug to be eliminated from the body.
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💊 4. Major Drug Categories and Examples
Drug Class Examples Use
Analgesics Morphine, Paracetamol Pain relief
AntipyreticsIbuprofen, Acetaminophen Fever reduction
Antibiotics Amoxicillin, Cefuroxime Bacterial infections
Antihypertensives Amlodipine, Losartan Lower blood pressure
Diuretics Furosemide, Hydrochlorothiazide Edema, hypertension
Antidiabetics Metformin, Insulin Control blood sugar
Antidepressants Fluoxetine, Sertraline Depression
Antipsychotics Haloperidol, Risperidone Schizophrenia, psychosis
Anticoagulants Heparin, Warfarin Prevent blood clots
Bronchodilators Salbutamol, Ipratropium Asthma, COPD
Antihistamines Diphenhydramine, Loratadine Allergy relief
AntiemeticsOndansetron, Metoclopramide Nausea and vomiting
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💉 5. Routes of Drug Administration
Route Abbreviation Description
Oral PO Swallowed and absorbed via GI tract
Sublingual SL Under the tongue (fast absorption)
Rectal PR Through the rectum (e.g., suppositories)
IntravenousIV Directly into the vein (immediate effect)
Intramuscular IM Into the muscle (moderate absorption)
Subcutaneous SC or SubQ Under the skin (slow and sustained release)
Topical — Applied to skin or mucosa
Inhalation — Breathed into lungs (rapid effect)
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⚠️6. Toxic Effects and Adverse Drug Reactions (ADRs)
Toxic Effect: Harmful result of either too much drug (overdose) or organ sensi-
tivity.
Type Example/Signs
Nephrotoxicity ↑ creatinine, ↓ urine output (e.g., aminoglycosides)
Hepatotoxicity Jaundice, ↑ ALT/AST (e.g., acetaminophen overdose)
Ototoxicity Hearing loss, tinnitus (e.g., furosemide, gentamicin)
Cardiotoxicity Arrhythmias, chest pain (e.g., doxorubicin)
Neurotoxicity Seizures, confusion (e.g., lithium, phenytoin)
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📏 7. Dosage Calculations
✴️Basic Formula:
\text{Dose} = \left(\frac{\text{Desired Dose}}{\text{Available Dose}}\
right) \times \text{Quantity}
💧 IV Flow Rate (gtt/min):
\text{Flow Rate} = \frac{\text{Volume (mL)} \times \text{Drop Factor (gtt/
mL)}}{\text{Time (min)}}
IV Pump Rate (mL/hr):
\text{Rate} = \frac{\text{Total mL}}{\text{Total hours}}
⚖️Weight-Based Dosing:
\text{Dose} = \text{mg/kg} \times \text{Patient Weight (kg)}
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✅ 8. The 5 + 3 Rights of Medication Administration
Right Purpose
1. Right patient Prevent giving meds to wrong person
2. Right drug Ensure correct medication
3. Right dose Prevent overdose or underdose
4. Right route Maximize effect and safety
5. Right time Maintain therapeutic level
6. Right documentation Accurate charting
7. Right reason Know the indication
8. Right response Monitor if the drug worked
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📖 9. Key Pharmacology Terms & Definitions
Term Definition
Bioavailability The fraction of administered dose that reaches systemic circu-
lation
Half-life (t½) Time it takes for plasma drug levels to reduce by half
Therapeutic Range The plasma concentration range in which the drug is ef-
fective but not toxic
Side Effect Secondary effect, usually predictable but undesired
Adverse Reaction Harmful or unintended effect at normal dose
Contraindication Condition in which a drug should not be used
Loading Dose Initial high dose to rapidly achieve therapeutic levels
Maintenance Dose Regular dose given to maintain desired drug levels
Drug Interaction When one drug affects the activity of another drug
Toxicity Condition of being harmful due to excessive drug levels or organ sen-
sitivity
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