Hello, Severe headaches are often caused due to lack of good sleep, dehydration, excess strain to the eyes, working for late hours in the computers, vision problem, anxiety, stressful lifestyle, addictions, etc. Medical conditions that cause such symptom is tension headache but some severe headache can be life threatening like vasculitis (inflammation of blood vessels), head injury(internal), stroke (due to blockage, bleeding), vasoconstriction syndrome, etc. You are suggested to stay well hydrated, take adequate sleep, get clinically examined by an ENT to detect any vision problem, you may need a pair of glasses. Avoid excessive exposure to sunlight & working long hours of laptop or PC. You should get clinically examined by a GP, get CT, MRI & X-ray done to detect any life threatening pathology. You will be treated accordingly. In the meantime, you can take acetaminophen (Tylenol), one SOS when needed. Rest in a comfortable, dim lighted room, hot or cold compression to the head or neck may help. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician