Patients with chronic daily headache, or those having more than three migraines per month that are not well-controlled, may be candidates for preventives. A preventive is chosen with regard to the type of headache and presenting comorbidities while keeping the medication dose and any side-effects to a minimum. Medication selection and dosing may require significant trial and error since what may work in one individual may not work in another. The doses often need to be adjusted and thus patience is necessary with these medications. Additionally it is very important that the physician be available for phone consultations pertaining to the patient’s headaches and medicine. In using such medication, a realistic goal is to decrease the tension headache severity by 70%, not to completely eliminate it.