Back left headache: what to know

Pain at the back left side may be linked to tight neck and scalp muscles, posture, or a migraine pattern. Allergic rhinitis, a common cold, or chronic sinusitis can cause head pressure with nasal symptoms. Dehydration and heat exhaustion may bring headache with thirst, weakness, dizziness, or heavy sweating. COVID-19 and dengue fever can also present with headache alongside other illness symptoms; fever, body aches, rash, or breathing symptoms should be reported. Anxiety can add muscle tension, but a new or unusual headache should not be dismissed for that reason.

Rest in a quiet, comfortably cool place, drink fluids if you can, and take breaks from screens. Gentle neck movement may help when posture or muscle tension is involved; stop if it increases pain. Note the onset, duration, location, triggers, fever, visual changes, nausea, and medicines used. Arrange medical advice if headaches recur, persist, change pattern, or follow a head injury.

Seek emergency care for a sudden explosive headache, weakness or numbness on one side, trouble speaking, confusion, seizure, fainting, severe drowsiness, vision loss, stiff neck with fever, or repeated vomiting. Get prompt assessment for severe headache with high fever, rash, dehydration, heat exposure, pregnancy, or a weakened immune system.

Ask whether the pattern fits tension, migraine, infection, or another cause, and which treatments are safe for you. Explain how quickly it started, whether neck movement affects it, your recent fluid intake and heat exposure, associated symptoms, and any previous headache history.