Short Notes on Headache
Number 8
Rebound Headache
Chronic daily headache (CDH) is a major medical problem. Surveys have shown that daily or almost daily headaches lasting longer than four hours are noted by one to two percent of the adult population in this country. They can occur at any age. From Vanderbiltthere was a case report of CDH beginning in a thirteen-month-old infant who was given acetaminophen for fever. One of the patients seen at the Vanderbilt Headache Clinic was 91-years-old female who presented a 60 year history of daily headaches. The patients come from all socio-economic groups. There is a slight predominance in females. If one were to total the expenses of their office and emergency room visits, their referrals to other doctors, their time as hospital inpatients, their laboratory and imaging studies, the cost of transportation to and from thesource of medical care, the medications and procedureswhich were prescribed and the time when they were not fully productive or absent from their school or work, it is estimated that this condition is a thirty five billion dollar a year drain on our economy.
CDH can be divided into two parts. The first and by far most common are the
daily or almost daily headaches which are the result of pain medications. Most people can take pain medications on a daily basis without developing headaches. For instance most people who take ibuprofen or other non-steroidal anti-inflammatory agents (NSAIDs) for joint pain, obtain improvement or relief of their pain and do not develop daily headaches. Approximately 2 – 4 % 0f patients who use daily NSAIDs for any reason develop CDH. The same holds true for patients taking daily opiates.
The second type of CDH are the very infrequent headaches that are not rebound headaches. These will be discussed in a later short notes on headache.
There at leasttwenty three phrases used in the medical literature to describe CDH. The Classification Subcommittee of the International Headache Society(IHS) uses only two of these –medication-overuse headacheandchronic migraine.This author thinks that both of these phrases are faulty.
The term “medication-overuse” might mislead the patient and care provider. Often the daily headaches might start when the patient uses one of the offending pain medications almost daily but continue after the patient switches to another type of analgesic or reduces the consumption of analgesics to one or two days a week. Physicians seeing the patient often ask how often pain medications are currently being taken and do not ask how often pain medications were being used when the daily headaches started. The package inserts which contain instruction for the dosing never describe once a week as overuse.
In the IHS description of chronic migraine, it states that medication overuse must have stopped two months before the diagnosis of chronic migraine can be applied. In the Vanderbilt Headache Clinic there were frequent patients who developed daily headache while taking daily pain medications but reported the headaches continued unchanged for many months or years after they reduced their pain medication to only one or two days a week. Others have noted their headaches gradually improved for several months after the medications were completely discontinued. Thus the “medication overuse” had ceased and the patient continued to have the combination of migraines and daily or almost daily tension-type headachesthat were later proved to be the result of their initial daily or almost daily pain medications.
In the Vanderbilt Headache Clinic and in a few reports in the literature there were very infrequent patients who described features of migraine as being present at least portions of each day. These patients were having “chronic migraine” but most reported their headaches started when they were using daily or almost daily pain medications. Their headaches gradually resolved after the offending agents were completely stopped. Thus they were proven to have an unusual presentation of what will be described below as rebound headaches.
This author prefers to diagnose the headaches resulting from dailyor almost daily pain medications as rebound headaches, a term used by Gallagher in 1983. It is easy to explain to the patient that the medications which have been used for today’s pain have “rebounded’ and caused their daily headaches.
There is no clinical laboratory test to establish the diagnosis of rebound. It must be suspected from the history and proven by the gradual recovery after all of the offending medications have been completely stopped. The patient’s history and both the general medical and thorough neurological examination must otherwise be negative, that is not point to any other etiology for the headaches. Being classified as a CDH the pain must be present more than 15 days per month. However almost all the patients with rebound have a headache five or more days each week. In previous years these patient might have experienced infrequent tension-type headaches and/or infrequentmigraines, the latter usually without aura.
About one-half of the patients can recall a prior injury, infection, arthritic condition or surgical procedure for which they started daily medications for pain. Occasional patients experience the onset of the daily headache after using acetaminophen for only four days for a respiratory infection. Many started their pain medications for a recent injury to the head, neck, low back or other portions of the body. Sometimes rebound follows medication being given for post-operative pain in the head or even the abdomen. In some the onset of daily headaches is weeks or even as long as six months after they had used the daily medications. The other half of the patients who present with frequent headaches that were later proven to be rebound cannot recall why they started the daily or almost daily analgesic agents.
The offending medications which can cause rebound are aspirin, acetaminophen, any of the NSAIDS with the exception of diclofenac and indomethacin, any opiate including the so-called non-addicting opiates, ergotamine, probably all of the triptans and caffeine. Quantity of the pain medication is not a factor. This author saw two patients with rebound who upon repeated questioning stated their daily headaches started and continued when they wereusing acetaminophen or ibuprofen only one or two days a week. Rebound headaches continue if the patient switches from one of the offending medications to another. Once established, rebound continues unchanged if the patient reduces their medications to only one or two days a week. Caffeine when consumed in high doses – 600+ mg (6 cups of coffee or 6 caffeinated soft drinks) daily – can cause rebound. Many of the patients using high dose caffeine note rapid recovery when they stop the caffeine and pain medications, at times becoming headache free by the fourth or fifth day.
After developing the daily or almost daily headaches, the patient often develop symptoms suggesting a psychiatric etiology. These include fatigue, sleep disturbances, depression, and a reduced quality of life. This often leads to unnecessary prescriptions of psychiatric medications which are ineffective. Many of the patients using NSAIDs develop hypertension resulting in antihypertensive therapy which fails to stop the headaches. About one half of the rebound patients get symptoms of fibromyalgia. It should be stressed that these problems follow the development of headaches. When dealing with comorbid problems physicians often fail to ask which came first. .
There are a few unusual presentations of rebound headaches which lead to erroneous diagnoses and therapy. At times the headaches are unilateral resulting in a suspicion of hemicrania continua. Hemicrania continua is a rare condition of unknown etiology that is quickly responsive to indomethacin. When a patient has continuous unilateral headaches, especially if there aremigrainous features, and there is no response after receiving indomethacin for a few days, the diagnosis is most likely rebound.
Headaches following minimal or major head or neck trauma are frequent but usually stop by the end of the eighth week. The IHSlabels these as acute post-traumatic headaches. Persistent post-traumatic headaches are rebound until proven otherwise. We reported a patient who was comatose upon arrival to the emergency room in another state. He had an intracerebral hematoma resulting in permanent hemiparesis. When seen in our headache clinic he had daily headaches of fifteen years duration that ceased after the pain medications where stopped.
Another unusual presentation was the seventeen month old infant who for two months had not eaten normally, preferring to sit in a darkened environment not displaying the normal infantile behavior and saying “head, ears, eye hurt”, always placing his hand on the same side of his head. The mother had given liquid acetaminophen and/or ibuprofen daily. The symptoms ceased after the analgesics were stopped.
The etiology of rebound headaches is unknown. It is not related to the amount of the offending agent. It is not an allergic disorder, since it can continue for months after the offending medication is discontinued. It is not an adverse event since the problem might continue if the patient switches to another of the offending agents. It probably is the result of biochemical changes that can occur in a small percentage of people who use one of the offending medications daily. There is one article pointing to a reduction of a serotonin receptor in the platelets of these patients. Further neurochemical studies are needed.
Treatment of rebound headache will be discussed in the next short notes on headache.
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