Headache is usually a benign symptom but it can be the manifestation of serious illness such as brain haemorrhage, brain tumour or brain infection. Approximately 5% of patients with headache are found to have a serious underlying neurological disorder.
Warning Symptoms/ When to get CT/MRI Brain 
- Acute severe & progressive headache.
- New onset headache in adult life (>40 years)
- Headache associated with fever, nausea, vomiting, vision disturbances, confusion, seizure, neck pain, limb weakness or worsens with posture and movements.
- Nocturnal occurrence or morning awakening. 
- Headache not responding to treatment 
Migraine: Most common form of headache, more common in females
- Episodic, throbbing
- Unilateral or bilateral 
- Nausea, vomiting 
-   Photophobia, Phonophobia
-  Positive family history
- Increased during menses, hunger, lack of sleep, glare, coffee, red wine, perfumes and stress
-   Relieved by sleep
-   Treatable with very few medicines
Prevention:-
- Visit to neurologist if any above symptoms or warning symptoms.
- Proper hydration.
- Avoid Stress.
- 	Do not take pain killers/analgesics by your own as it leads to increase in headache frequency.
- Proper treatment of hypertension.
Dr Gourav Jain, MD, DM Neurology (PGI Chandigarh)
Consultant, Neurologist