Patients who use medications for headache more than twice weekly are at risk of medication overuse headache. Any analgesic, including triptans themselves, can contribute, but opiates and barbiturates are the main culprits. In this setting, the migraine may "transform" into a chronic daily headache. Medication overuse headaches usually start in the morning and improve but do not completely resolve with analgesic therapy. The patient must completely discontinue the offending drug for 2 to 12 weeks for the headaches to resolve. Treating headaches during the period of abstinence can be very difficult. The physician should be vigilant about the development of another cause of headache (mass lesion, inflammatory disorder) in a patient with transformed migraines. CNS imaging and laboratory workup, not generally recommended in the patient with typical migraine, are sometimes indicated. In this patient without focal neurological findings, however, the most likely diagnosis is still medication overuse headache. Status migrainosus (continuous migraine) and CNS vasculitis are much less common than medication overuse headache. Pseudotumor cerebri usually causes papilledema.