Pearson SM, et al. - Researchers evaluated acute cluster headache treatments in a large international sample (including recommended options such as oxygen, commonly used medications such as opioids, and emerging medications such as intranasal ketamine) in terms of their effectiveness and adverse effects. They particularly focused on a large subset of respondents 65 years of age or older. Data was presented from the Cluster Headache Questionnaire, with respondents from over 50 countries with the vast majority from the US, the UK, and Canada. In the questionnaire, 3,251 people participated, of which 2,193 met criteria for this study (1,604 cluster headache and 589 probable cluster headache). As per survey respondents, oxygen is a highly effective treatment with few complications in cluster headache in this large international sample, including those 65 years or over. In addition, triptans were identified as very effective with some side effects. Findings suggest that patients with probable cluster headache and those with a full diagnosis of a cluster headache may respond similarly to acute medications.