High-altitude headache: Insights into pathophysiology and potential treatment implications.
J Physiol 2026 Jun 03. [Online ahead of print]

Abstract

High-altitude headache (HAH) is the most common neurological manifestation triggered by hypoxia during rapid ascent above 2500 m, often presenting as an isolated symptom or as part of acute mountain sickness (AMS). HAH shares clinical features with migraine, cluster headache and other primary headache, complicating differential diagnosis. Prevalence varies widely depending on ascent speed and altitude, with higher rates observed in populations ascending rapidly by passive transport and lower rates in those ascending gradually on foot. Controlled normobaric hypoxic chamber studies confirm hypoxia as a potent trigger, with most participants developing HAH within hours. Environmental factors, including fluctuations in barometric pressure, further contribute to headache onset. We propose that the pathophysiology involves activation and sensitization of the trigeminovascular system, with key molecular mediators such as nitric oxide, adenosine, calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) playing central roles. Hypoxia stabilizes hypoxia-inducible factor-1α (HIF-1α), driving transcriptional changes that can prime vascular and neuronal pathways for head pain. Although HAH typically responds to simple analgesics and oxygen, its similarity with migraine suggests that targeted therapies against CGRP and PACAP may offer additional benefits. Future research should clarify the mechanistic continuum between HAH and AMS and evaluate multitarget therapeutic approaches.

Authors+Show Affiliations

Falla M0000-0001-7477-3020Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy. Center for Mind/Brain Sciences - CIMeC, University of Trento, Rovereto, Italy. Mountain Clinic, Eurac Research, Bolzano, Italy.
Frank F0000-0002-7236-5557Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria.
Strapazzon G0000-0002-4402-8633Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy. Mountain Clinic, Eurac Research, Bolzano, Italy. Department of Medicine - DIMED, University of Padova, Padova, Italy.
Lawley J0000-0003-2166-7966Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy. Institute of Sport Science, Performance Physiology and Prevention, University of Innsbruck, Innsbruck, Austria.

Pub Type(s)

Journal Article
Review

Language

eng

PubMed ID

42231830