[Nitroglycerin-induced headaches].

INTRODUCTION: Headache is the most prominent side effect of nitrate therapy. Lack of compliance is usually associated with headache which has a detrimental effect on quality of life. In spite of the high frequency of this adverse effect, the headache characteristics, timing and risk factors are less known. On the other hand, intravenously administered nitroglycerin-induced migraine attack is a common human research model in migraine. AIM OF THE PRESENT STUDY: to evaluate the headaches occurring after administration of therapeutic dose of sublingual nitroglycerin, in migraineurs and controls.

METHOD: Twenty-eight female migraine patients without aura and 14 healthy controls received 0.5 mg nitroglycerin. Headache intensity and characteristics have been investigated for 24 hours.

RESULTS: two types of headache developed after the nitroglycerin administration: (1) an immediate headache that does not fulfil the criteria for migraine, mild and disappears spontaneously within 1 hour; (2) a typical migraine attack without aura develops several hours after the nitroglycerin administration (mean latency: 250 min), moderate or severe, and warrants antimigraine therapy. The two types of headache developed independently. The nitroglycerin-induced headaches have not been determined solely by the previous migraine diagnosis, although both immediate (p = 0.0045) and typical migraine headache (p = 0.00047) were significantly more frequent among migraineurs compared to controls. Moreover, those control subjects who experienced migraine attacks had predispositions to migraine. Previous results of the authors supported that lower platelet serotonin concentration and higher plasma CGRP concentration, during the headache free period, are risk factors that express greater susceptibility to develop both spontaneous and nitroglycerin-induced migraine attack.

CONCLUSION: Authors suggest an accurate exploration of the headache case-history before nitroglycerin treatment. This makes it possible to give proper information to migraine patients and possible migraine patients, and thus suitable treatment can be offered if needed.