La pharmacologie est l'étude des médicaments : leur mécanisme d'action, leur devenir dans l'organisme, leurs effets thérapeutiques et leurs effets indésirables. Pour l'infirmière, la pharmacologie est au cœur de la sécurité des soins — administrer un médicament exige bien plus que lire une étiquette.
Key concepts
- Pharmacocinétique (ADME) : Absorption → Distribution → Métabolisme → Élimination
- Pharmacodynamie : mécanisme d'action du médicament (agoniste = active un récepteur, antagoniste = le bloque)
- Règles des 8 « bons » : bon patient, bon médicament, bonne dose, bonne voie, bon moment, bonne documentation, bon motif, bonne réponse
- Index thérapeutique : rapport entre dose toxique et dose efficace — étroit = risque élevé (digoxine, lithium, warfarine)
- Interactions médicamenteuses : synergie (effet accru) vs antagonisme (effet réduit) vs toxicité additive
Intro Pharmacology
Understand how drugs interact with the body at the receptor level: the foundation for medication safety.
Drug-Receptor Basics
How medications produce their effects
Most drugs work by binding to receptors on cells. The drug-receptor interaction determines whether the drug activates or blocks a cellular response.
Agonist
Binds to receptor and ACTIVATES it. Mimics the natural ligand. Example: Morphine (opioid agonist)
Antagonist
Binds to receptor and BLOCKS it. Prevents the natural ligand from activating. Example: Naloxone (opioid antagonist)
Clinical Connection
Naloxone reverses opioid overdose by competing for the same receptors. It's an antagonist that displaces the agonist (morphine/fentanyl) from opioid receptors.

Drug absorption routes showing how medications enter systemic circulation through different pathways
Pharmacokinetics Overview
What the body does to the drug

Pharmacokinetics: the four-step journey of a drug through absorption, distribution, metabolism, and excretion
Pharmacology Check
1/10An AGONIST drug at a receptor will:
Pre-nursing comprehensive review
1/20Which organelle contains its own DNA and is inherited exclusively from the mother?
