Altitude Sickness

Dr Danny Marhaba
Emergency Registrar

Peer Reviewer: Dr David McCreary

Weekly Advanced Group teaching at the Alfred includes a lightning learning presentation from one of our registrars. From time to time, we’ll ask them to record these talks to share their teaching with the FOAMed world.

This week featured a great talk from Dr Danny Marhaba on Altitude Sickness. Albeit not a presentation we will see often in Australia, but an important one nevertheless – particularly if you are expedition-medicine-inclined.

In summary:


HAH: High Altitude Headache (An isolated headache due to hypoxic cerebral vasodilation).

AMS: Acute Mountain Sickness (HAH + Vomiting / Dizzyness / Insomnia).

HACE: High Altitude Cerebral Edema (Ataxia or AMS).

HAPE: High Altitude Pulmonary Edema.



  • Every 500m Ascent, sleep 1 night at that level (can sleep 4 nights at 2000m as an exception).
  • Acetazolamide 125mg PO BD started the day before ascent.
  • Low flow oxygen 2-4L/min.
    • If HAPE, vary oxygen and positive airway pressure aiming sats >90%.
  • Start with NSAIDs for headache.
  • Use Ondansetron for nausea and vomiting.
  • If HACE (ataxia, somnolescence, confusion) use Dexamethasone 8mg IM/PO once, then 4mg q6h.
  • If HAPE (dyspnoea, ++ sputum) use Nifedipine 10mg SL once then 60mg daily split in 2 or 3 doses.
  • If headache or AMS, stop the ascent.
  • If signs of HACE or HAPE. Call for help and Descend >300m if HACE, >1000m if HAPE.
  • If descent is challenging can trial a portable hyperbaric chamber or call for retrieval.

Want to read more?

The Emergency Care Institute website had a great and detailed summary here

This review from the New England Journal of Medicine


Danny Marhaba

Danny Marhaba

Emergency Registrar, Alfred Health

Danny is an Emergency Medicine Registrar at the Emergency and Trauma Centre.

He trained in regional NSW before moving back to Melbourne to complete his training at the Alfred.