Extensive Morphine Flashcards

Drug Class & Pharmacology

Q: What class of drug is morphine?
A: Narcotic analgesic (opioid).

Q: How does morphine work pharmacologically?
A: Binds to opioid receptors in the CNS → alters pain perception & emotional response → causes analgesia, sedation, respiratory depression, vasodilation, ↓ gag reflex, ↓ AV node conduction .

Indications

Q: What are the QAS indications for morphine?
A:

  • Significant pain

  • Sedation

  • Autonomic dysreflexia (SBP > 160 mmHg)

Contraindications

Q: What are the contraindications for morphine?
A:

  • Allergy/adverse drug reaction

  • Kidney disease (renal failure)

Precautions

Q: What precautions must be considered with morphine?
A:

  • Hypotension

  • Respiratory tract burns

  • Respiratory depression/failure

  • Known addiction to narcotics

  • Concurrent MAOI therapy

  • Cardiac chest pain

Side Effects

Q: What are the common side effects of morphine?
A:

  • Bradycardia

  • Drowsiness

  • Hypotension

  • Nausea/vomiting

  • Pinpoint pupils

  • Respiratory depression

Onset, Duration & Half-life

Q: What is the onset of action of morphine (IV vs IM)?
A:

  • IV: 2–5 minutes (peak 20 min)

  • IM: 5–10 minutes (peak 20–30 min)

Q: What is the duration of action of morphine?
A: 1–2 hours

Q: What is the half-life of morphine?
A: ~2 hours

Presentation

Q: How is morphine presented for QAS use?
A: Ampoule, 10 mg/1 mL morphine sulphate pentahydrate

Schedule

Q: What schedule drug is morphine?
A: Schedule 8 (S8 – Controlled drug)

Routes of Administration

Q: What routes can morphine be given by QAS?
A: IV, IM, IO, SUBCUT (with approval)

Adult Doses (Significant Pain/Autonomic Dysreflexia)

Q: What is the IV/IO morphine dose for adults <70 years?
A: 2.5–5 mg IV/IO, repeated at up to 5 mg every 5 min. Max 20 mg (or MME)

Q: What is the IV/IO morphine dose for adults ≥70 years, frail, or cachectic?
A: 2.5 mg IV/IO, repeated every 5 min. Max 10 mg (or MME)

Q: What is the IM morphine dose for adults <70 years?
A: 2.5–10 mg IM, repeated every 10 min (max 20 mg or MME)

Q: What is the IM morphine dose for adults ≥70 years, frail, or cachectic?
A: 2.5–5 mg IM, repeated every 10 min (max 10 mg or MME)

Paediatric Doses

Q: What is the IV/IO morphine dose for children ≥1 year?
A: 100 mcg/kg, single max 2.5 mg; repeat 50 mcg/kg (max 2.5 mg) every 5 min. No maximum total dose

Q: What is the IM morphine dose for children ≥1 year?
A: 100–200 mcg/kg, single max 5 mg. Repeat 100 mcg/kg (max 2.5 mg) every 10 min. Total max 200 mcg/kg (or MME)

Q: Can QAS give morphine to paediatric patients with cardiogenic chest pain?
A: No, it is not authorised

Special Notes

Q: What must be considered if morphine and fentanyl are both used?
A: The combined dose must be calculated in Morphine Milligram Equivalents (MME). Example: 10 mg morphine + 100 mcg fentanyl = 20 mg MME

Q: What special consideration is required if morphine is given to a hypotensive patient?
A: IV increments must be ≤2.5 mg, IM ≤5 mg, and ACPs must call for CCP backup if available

Q: Why must hospitals be notified when morphine is given to a woman in labour?
A: Morphine crosses the placenta rapidly → neonatal respiratory depression possible. Paediatrician may need to attend delivery

Q: Can morphine and midazolam be mixed in one syringe?
A: No, they must not be mixed. If co-administered, manage for potential hypotension