[header] How to relieve a hypertension headache [title] Take an over-the-counter pain reliever. [step] Either ibuprofen or acetaminophen are good options and readily available at any pharmacy. As soon as you feel a headache developing, take the maximum dosage allowed on the label. 
Then, repeat the dosage, as directed, until the pain subsides. Experiment with various otc medications to see which one works the best for you.