Medication overuse headache may be confused with Cluster headache

The definition of Cluster headache is listed here because it is often times confused with migraine with aura type patients who are over treating and have medication overuse headache.  The ICD 3 lists Cluster Headache as a trigeminal autonomic cephalalgia, which is an entity separate from migraine, although they have many similar features.  Many persons with cluster headache have family members with migraine, just like migraine patients commonly have a history of migraine in their family .  Cluster headache predominates in men, four times as frequent as in women.  The age range is usually mid- twenties to about sixty.  These are very severe, quick onset, one sided headaches which consist of pain around the eye, temple, or cheek.  There may be characteristic accompanying symptoms on the side of the face, such as: drooping of the upper eyelid, smallness of one pupil, sweating above the eye, redness of the eye, tearing of one eye, nasal congestion or drainage of clear fluid.  The headaches come in time periods called clusters which usually last 6-8 weeks and consist of 1-8 headaches a day, lasting 20-40 minutes.  The patient usually gets up and paces around the room.  Migraine patients usually lie down and don’t like to be up and about.  Nausea, vomiting, and sensitivity to light and sound may occur with cluster headache, but are not as prominent as that which occurs with migraine.  The onset to peak of cluster headache is very quick—often in minutes.  The headaches may track the clock, coming at the same time every day and they may characteristically occur one to two hours after going to sleep.  During the cluster period drinking alcohol may aggravate the headache, but not at other times.  The patients often have a driven, type A workaholic nature.  Cluster headaches may be further described as episodic or chronic, depending on their frequency.  About 10 % of cluster headache patients have a chronic cluster pattern.

As noted by the description of migraine and cluster headache, they really are very different medical problems.  Migraine and medication overuse headache are very common in the clinic, while cluster headache is relatively rare.  Since cluster headaches may occur daily or multiple times a day, for several months, they are confused with medication overuse headache which also may come daily, but sometimes every day for 6 months or several years which only comes with chronic cluster.  The onset to peak time for cluster headache which is usually minutes, is different from migraine which make take an hour or two to max out to the peak.  Also cluster headache has true headache free times between the attacks, which is rare with medication overuse headache patients who usually always have some mild grade 1-4 headache present, and then the severe headache starts from there.  Also cluster headaches are typically locked onto one side of the head and usually don’t switch sides, while migraine amped up to medication overuse headache may switch sides and commonly comes in the back of the head or the neck on one side.  The other autonomic features of cluster headache, such as tearing, eyelid drooping, injection of the conjunctiva on one side, one side of the head nasal dripping and forehead sweating, should be a giveaway to the cluster pattern.  Lastly, the fact that cluster headaches may occur locked into certain times, like every night at 2:00 AM, or at 10:00 PM, should make the penny drop for the diagnosis of cluster headache.

Read the individual articles on Medication Overuse Headache and Cluster Headache.