My daughter has had headaches on and off for the past year and a half. Everything we have tried has helped a little, but they always come back. What could be the cause?

The most common cause of an undiagnosed recurrent headache in a child is a childhood migraine. Migraines in childhood are defined as recurrent headaches with at least three of the following features: specific location of pain, throbbing headache, relief with sleep, abdominal pain, nausea or vomiting, an "aura"--this could be changes in vision or tingling of the hands and feet--or a family history of migraines. Some kids do have abdominal migraines--they have stomachache without the headache.

Usually migraine treatment starts with ibuprofen, but if that doesn't control them, there are a number of stronger drugs available to treat and/or prevent them. Also, biofeedback machines and self-hypnosis can really work for migraines.

Allergies, sinus infections, mono, dehydration and stress are other common causes of recurrent headaches. Many parents are also concerned about a less common cause for recurrent headaches: brain tumors. Headaches that awaken children or early morning headaches are the greatest concern, especially if they are accompanied by vomiting or other neurological symptoms.

The best thing is to know what type of headaches your daughter has. Sometimes bringing your doctor a “headache diary” -- where you keep track of the date, time, type of headache, and what made it go away -- can help your doctor correctly diagnose the type of headache. Also, a visit to a neurologist may help make the diagnosis and help find the best type of treatment.