Headaches in kids are more common than most of us appreciate; perhaps 4% of all children have chronic headaches. Trauma is a common cause from injuries. Misalignment of the spine is a common finding, especially in the cervical spine. Stress is common for most kids; life has become very complicated and difficult to balance. Home life is common as well with siblings, dysfunctional parents. Insomnia or nightmares are common too.
Medical problems such as tumors, high blood pressure, sinus congestion from allergies or household chemicals, caffeine addiction, and eye strain must also be considered.
Drugs are not a great way to treat headaches in anyone because drugs do not treat the underlying cause. A good workup is important before treatment is started, whether using drugs or other therapies.