Brief Answer: Commonest cause is migraine. Detailed Answer: Hi, Thank you for posting your query. The most common cause of headache in your sister could be migraine. In migraine, headache can be severe, and associated with nausea or vomiting. Increased sensitivity to light and noise may be present. For pain relief, she can take diclofenac or rizatriptan tablets. If headaches are frequent, then, preventive medications such as flunarizine, beta blockers or topiramate may be used. If headache does not get better, then, brain scan such as CT or MRI scan may be done. I hope my answer helps. Please get back if you have any follow up queries or if you require any additional information. Wishing you good health, Dr Sudhir Kumar MD (Internal Medicine), DM (Neurology) XXXXXXX Consultant Neurologist Apollo Hospitals, Hyderabad, India Click on this link to ask me a DIRECT QUERY: http://bit.ly/Dr-Sudhir-kumar My BLOG: http://bestneurodoctor.blogspot.in

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