🌿 Cluster headaches are rare — but for the people who experience them, they can be devastating. They’re very different from an ordinary headache. Cluster headache attacks typically cause severe pain on one side of the head, often in or around one eye, and can come on very quickly. An individual attack may last anywhere from 15 minutes to 3 hours, and during an active cluster period they can happen more than once a day. (nhs.uk) Other symptoms can occur on the same side as the pain, including: • a red or watering eye • a blocked or runny nose • a drooping or swollen eyelid • a smaller pupil • facial sweating • restlessness (nhs.uk) One particularly unusual feature is their timing. Attacks can occur at remarkably similar times each day, and many happen at night. Mayo Clinic notes that nighttime attacks commonly occur around 1–2 hours after going to bed and can wake someone from sleep. (Mayo Clinic) Because cluster headaches can share symptoms with other headache disorders, getting...