A new, autosomal dominantly inherited syndrome with a bleeding disorder was described in 1985 by Stormorken and his co-workers. In this multifaceted syndrome, there were the following integral components: thrombocytopathia, extreme miosis with Argyll Robertson-like traits, muscular fatigue, a tendency to spasms, asplenia, ichthyosis, dyslexia, etc. Headache with migraine traits was also present in the family in all 4 generations in which this syndrome had been observed. Nasal and conjunctival bleeding were part of the headache picture in some of the individuals exhibiting the hemorrhagic syndrome. While the attack-related bleeding disturbances only involved family members who also suffered from the hemorrhagic syndrome, the headache per se may seem to behave differently: The affected son's headache seems to have developed into a headache with tension headache traits, whereas the other, unaffected, son's headache has common migraine traits. The familial headache which in earlier generations clearly had migraine traits, therefore, may be inherited independently from the hemorrhagic disorder. In other words, a migraine or migraine-like headache is most probably not an obligatory integral part of this syndrome. The thrombocytopathia in this disorder comprises abnormal serotonin storage, uptake, and release (Stormorken and co-workers, to be published). The admittedly somewhat farfetched possibility also exists that the headache, although being similar to migraine, differs essentially from it and may be an expression of the serotonin aberration.