What symptom can appear with a cluster headache?

Cluster headaches are known for several specific symptoms that can be quite debilitating. One of the hallmark features of cluster headaches is unilateral, intense pain typically located around or behind one eye. In addition to this pain, patients often experience autonomic symptoms on the same side as the headache, which can include nasal congestion. This occurs due to the activation of the trigeminal nerve and the resultant changes in blood vessel dilation and other vasodilatory effects that lead to mucus production and nasal obstruction.

While symptoms like photophobia (sensitivity to light) and pulsating pain are more commonly associated with migraine headaches, and visual aura is linked primarily with migraine occurrences, nasal congestion can occur during cluster headaches due to the associated autonomic symptoms. Understanding the context of the autonomic involvement helps clarify why nasal congestion is a key symptom of cluster headaches, distinguishing it from other types of headaches such as tension or migraine.