This headache isn't the kind that you pop some over-the-counter meds and it goes away. If you're getting severe headaches with no prior history of migraines, high blood pressure may be to blame. Extremely high blood pressure, known as malignant hypertension, puts pressure in the cranium (the part of the skull that encloses the brain). As blood pressure rises, pain builds in the cranium. That causes severe headaches.
Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol. 2018;71(19):e127-e248. PMID: 29146535 www.ncbi.nlm.nih.gov/pubmed/29146535.