One-sided headache on the left: what to know

Migraine may cause throbbing or pulsating pain with nausea, vomiting, or sensitivity to light and sound. Tension-type pain is often pressing or tight and may involve the neck. Nasal blockage or facial pressure can occur with Allergic Rhinitis, Chronic Sinusitis or a Common Cold. Fever and body aches may accompany COVID-19 or Dengue Fever. Dehydration, Heat Exhaustion, poor sleep, missed meals, eye strain and stress can also trigger head pain. The location alone cannot identify the cause.

Rest in a quiet, dim room, drink fluids, eat if you have missed a meal, and reduce screen glare. Record when the pain began, how long it lasts, its severity, triggers, and symptoms such as nausea or visual changes. Use a familiar pain medicine only as directed on its label and avoid taking it repeatedly without medical advice, because frequent use can keep headaches going. Arrange a clinical assessment if headaches recur, change pattern, or interfere with normal activities.

Seek emergency care for a sudden, severe headache, new weakness or numbness, trouble speaking, confusion, fainting, a seizure, loss of vision, a stiff neck with fever, or a headache after a significant head injury. Seek prompt medical advice if the pain is new and persistent, steadily worsening, associated with repeated vomiting or high fever, or occurs during pregnancy or after childbirth.

Could this pattern fit migraine, tension-type headache, sinus disease or another cause? Which warning symptoms should prompt urgent care? How should I use pain relief safely, and do I need an examination or further testing?