High altitude nausea: causes and care

High altitude nausea is managed by stopping ascent, resting, taking small sips, eating lightly, and descending if symptoms persist or worsen. Do not force food or large amounts of fluid, and avoid alcohol while you are unwell.

Lower air pressure at altitude means less oxygen is available to your body, and nausea can be part of acute mountain sickness. It may accompany headache, dizziness, fatigue, or reduced appetite after ascent. Food poisoning, gastroenteritis, heat exhaustion, reflux, gastritis, or low blood sugar can cause similar symptoms, especially if there is diarrhoea, fever, abdominal pain, sweating, or a clear link with meals.

Stop climbing and rest somewhere cool and safe. Take frequent small sips of water or an oral rehydration drink; pause if drinking triggers vomiting. Try bland food when able, such as toast or rice, and avoid heavy meals. Do not travel higher while nausea continues. If symptoms fail to improve with rest, arrange a descent and contact a clinician. Medicines for nausea are not suitable for everyone, so check before using one.

Get urgent help for repeated vomiting, inability to keep fluids down, confusion, marked drowsiness, difficulty walking, fainting, severe headache, or breathlessness at rest. Descend with support if altitude illness is suspected. Severe abdominal pain, blood in vomit or stool, a high fever, or signs of dehydration such as very little urine also need prompt medical assessment.

Ask how quickly you should ascend, whether any planned medicine is appropriate for you, and what symptoms mean you should descend. Tell the clinician about vomiting, diarrhoea, fever, diabetes, pregnancy, and medicines that you take.