Bright lights can cause headaches for reasons similar to too little light: the eyes are forced to adjust to brightness levels that are not optimal for them. Some people who are particularly affected by bright lights find they even trigger migraines.
Not surprisingly, removing the trigger is the best way to ease a headache caused by bright lights. Go into a dark room or cover the face and let the eyes relax. OTC medications can also help alleviate the headache more quickly.

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