Antipyretics & Analgesics: Summary

Definitions

  • Analgesic:
    • From Greek words "an" (without) and "algos" (pain).
    • Categorized into non-opioids, opioids, and adjuvant analgesics.
  • Antipyretic:
    • From Greek "anti" (against), Latin "pyreticus," and Greek "puretos" (fire/fever).

WHO Analgesic Ladder

  • Steps:
    • Step 1: Mild pain; non-pharmacological approaches, paracetamol.
    • Step 2: Moderate pain; NSAID and/or oral opioid.
    • Step 3: Severe pain; increased dose of an oral opioid or IV/SC opioid or IN fentanyl.
  • Advantages:
    • Good for short-term management of acute pain.
    • Simple, safe (lowest dose first), emphasizes drug combinations.
  • Disadvantages:
    • Too simplistic for chronic pain, lacks guidance on formulations.
    • Opioids have adverse effects; may not suit all patients.
    • Pain management should be individualized.

Paracetamol (Acetaminophen)

  • Trade Names: Panadol, Tylenol, Panamax, Dymadon
  • Mechanism of Action: Inhibits peroxidase, preventing COX activation.
  • Indications: Fever, mild-to-moderate pain.
  • Side Effects/Adverse Effects:
    • Overdose can cause severe liver injury, increased by fasting/alcohol use.
  • Nursing Considerations:
    • Caution with liver disease; overdose treatment within 10 hours.
    • Soluble preparations contain sodium.
    • Not for infants under 1 month.

Ibuprofen

  • Class: Non-steroidal anti-inflammatory drug (NSAID)
  • Trade Names: Neurofen, Advil, Motrin, Caldolor
  • Mechanism of Action: Inhibits prostaglandin synthesis by inhibiting cyclo-oxygenase (COX).
  • Indications: Pain (especially inflammation/tissue injury), fever.
  • Side Effects/Adverse Effects:
    • Nausea, dyspepsia, GI ulceration/bleeding, raised liver enzymes.
  • Nursing Considerations:
    • Take with food to prevent GI irritation.
    • Assess for allergies, asthma, gastric issues before starting.
    • Monitor for bleeding if administered preoperatively.
    • Contraindicated in peptic/GI ulceration, bleeding disorders, severe liver/kidney/cardiac failure, post-CABG.

Morphine

  • Class: Opioid analgesic
  • Trade Names: Morphine sulfate, Zomorph, Sevredol, Morphgesic, MXL, Oramorph
  • Mechanism of Action: Acts at mu-opioid receptors in the CNS.
  • Indications: Severe pain.
  • Side Effects/Adverse Effects:
    • Nausea/vomiting, drowsiness, dizziness, constipation, respiratory depression.
  • Nursing Considerations:
    • Ensure correct strength is selected.
    • Rotate injection sites.
    • Monitor respiratory function.
    • Chronic use may lead to tolerance/dependence.