Comorbidity or combination – more evidence for cluster-migraine?

Background While migraine and cluster headache share some clinical features and therapies, they differ considerably in the frequency and duration of the headache, as well as the inter-attack, or inter-bout, pathophysiology. Neither is fully understood, with their shared pathways being of interest. Findings Five patients for whom it was difficult to distinguish migraine from cluster headache are presented. They had aspects of their phenotypes, which could be attributed to both disorders. Each patient was thoroughly examined, excluding secondary causes of headache, and had been treated with a number of medicines. Conclusion A correct diagnosis is key to the appropriate treatment approach. Especially, if treatment is not successful for the suspected headache type, and enlargement of the diagnostic and therapeutic range, respectively, should be evaluated. Whether in such settings there is shared or different pathophysiology can only be speculated upon.