Age

18–any

Sex

ALL

Healthy volunteers

Not accepted

Age ≥18 years
Presentation to the emergency department with acute non-traumatic headache of less than 72 hours duration
Diagnosis consistent with a primary headache disorder, including:
* Migraine
* Tension-type headache
* Cluster headache (according to ICHD-3 criteria)
Moderate to severe pain intensity (VAS ≥5/10)
Ability to understand the study procedures and provide informed consent

Suspected or confirmed secondary headache (e.g., intracranial hemorrhage, infection, mass lesion)
Recent head trauma
Known hypersensitivity or contraindication to magnesium sulfate or paracetamol
Use of analgesic medication within the previous 6 hours
Pregnancy or breastfeeding
Severe renal insufficiency or conditions contraindicating magnesium administration
Hemodynamic instability or clinically significant cardiac conduction disorders Prior participation in this study

High- vs Standard-Dose Intravenous Magnesium for Acute Headache