High blood pressure, along with vomiting and headache, can happen due to stress, migraine, infection, dehydration, uncontrolled blood pressure, or other medical conditions. Because these symptoms together may sometimes indicate a serious problem, avoid starting blood pressure medicines or painkillers on your own without checking your blood pressure and understanding the cause. Rest in a calm place, drink small amounts of fluids to prevent dehydration, and avoid oily or heavy foods until vomiting improves. If you already take blood pressure medicine regularly, continue it as prescribed unless a doctor advises otherwise. Paracetamol may help mild headaches if suitable for you, but repeated vomiting, very high blood pressure, chest pain, blurred vision, confusion, weakness, or severe headache require urgent medical attention. A doctor may need to examine you and check your blood pressure, hydration, and possible causes before deciding the safest treatment or medicines for your symptoms.