“About half of people with chronic headache also has medication overuse.”
In 2009 30,000 persons aged 30-44 were interviewed.
Those with self-reported chronic headache were invited to be interviewed by a neurology resident.
What they found:
The majority of those with migraines also had medication overuse, and about half of those with neck related or tension type headaches had medication overuse
More than 70% of those with medication overuse had headaches with chronic tension-type characteristics.
The definition of overdose varies depending on the drug, but generally it is "medication taken on 10 or more days a month on a regular basis for three or more months."
With medication overuse it is not uncommon for the medication itself to be contributing to the patient’s headaches.
It seems that medication as an intervention is not a long-term solution.