Lecture on Nervous System Medications: Analgesics

Key Topics Covered

Acetaminophen (Tylenol)
- Uses: Mild to moderate pain, fever relief
- Mechanism: Inhibits prostaglandin synthesis in the CNS
- Side Effects:
  - Hepatotoxicity with large doses (Black Box Warning)
  - Maximum dosage: 4 grams per day
- Patient Education:
  - Monitor for acetaminophen in over-the-counter products
  - Antidote for overdose: Acetylcysteine

Common NSAIDs: Ibuprofen, Naproxen, Ketorolac, Indomethacin
- Uses: Mild to moderate pain, fever, inflammation
- Mechanism: Inhibits prostaglandin synthesis
- Side Effects:
  - GI upset, GI bleeding
  - Renal toxicity
  - Rash, headache
- Contraindications:
  - Peptic ulcer disease, bleeding disorders
- Patient Education:
  - Avoid alcohol (increases risk of GI bleed)
COX-2 Inhibitor: Celecoxib (Celebrex)
- Uses: Osteoarthritis, Rheumatoid arthritis
- Mechanism: Inhibits COX-2 enzyme, reducing prostaglandin synthesis
- Side Effects:
  - Thrombosis risk (MI, stroke)
  - GI bleeding, rash
- Contraindications: Allergy to aspirin, NSAIDs, sulfenamides

Aspirin
- Uses: Pain, inflammation, fever, Kawasaki disease, MI prevention
- Mechanism: Inhibits prostaglandin synthesis, decreases platelet aggregation
- Side Effects:
  - Tinnitus (ringing in ears)
  - GI upset, GI bleeding
  - Rash
- Contraindications:
  - Peptic ulcer disease, bleeding disorders
  - Children with fever (risk of Reye's syndrome)
- Signs of Salicylism: Tinnitus, nausea, vomiting, respiratory alkalosis
- Memory Aid: "ASPIRIN"
  - A: Abdominal pain (GI upset)
  - S: Salicylism
  - P: Peptic ulcer disease
  - I: Intestinal blood loss (GI bleed)
  - R: Reye's syndrome
  - I: Itchy rash
  - N: Noise (tinnitus)