Learn how to get around rebound headache
Duration not related to time of drug in body
Giving preventive medications to a patient who is overusing acute medication for headache may be a waste of time, according to a presenter at the American Society of Health-System Pharmacists Midyear Clinical Meeting.
In fact, the six to eight weeks that the preventive medications take to become effective does not begin until the patient is no longer using the headache medications, says Carla R. Rubingh, PharmD, assistant professor of the department of pharmacy practice, University of Nebraska Medical Center in Omaha. Rubingh's presentation, "Getting around rebound," was part of the meeting's "Clinical Pearls" section.
Medication overuse is the No. 1 cause of chronic daily headache, she says. Chronic daily headache is defined as headache that occurs more than 15 days in a month. Medication overuse headache can present as a dull, squeezing pain, usually in the frontal region of the head.
All acute medications used for the treatment of headache can cause rebound, with the possible exception of nonsteroidal anti-inflammatory medications, Rubingh says. To avoid this, no acute medication should be used more than three days per week. "This is not the number of doses. This is the number of days."
Patients may wonder why they quit taking a medication such as Excedrin for two weeks, and their headache did not get any better. The duration of rebound headache is not related to the duration of the drug in the body, Rubingh says. "You cannot calculate how long it should take for the drug to wash out of the body."
Physiological changes occur in the brain depending on what drug the patient is overusing, she explains. "Rebound can last anywhere up to a year."
Because of this, all patients should be monitored for the frequency of the use of these medications and the doses it takes to get relief. Administration of preventive therapy should be done at the time you start to taper the overused medications, Rubingh says. Support medications can be started at that time, too.
Most important is patient education. Patients, she says, should be told at the beginning that these drugs should not be used more than three days a week.