[Can the biologic pattern of cervicogenic headache change after overuse or withdrawal of ergotamine derivatives?].

The transformation of a primary headache into a chronic daily headache (CDH) may or may not be related to the overuse of pain-killers, as their influence on the pathophysiological mechanisms remain inconclusive. We describe three patients (female, aged 65 and 39 years, and male, 46) affected by cervicogenic headache (CH) and CDH linked to the overuse of pain-killers (ergotamine derivatives) that were submitted to the infiltration of the greater occipital nerve (GON). At the end of three days of treatment, a total improvement of the pain symptoms was recorded, which allowed for the withdrawal of the ergotamine derivatives. The CH cannot be ranked with the CDHs, since it presents an organic etiology; however, if the pain is daily and the diagnosis is belated, the indiscriminate and excessive use pain-killers may occur. In the cases described, the overuse of pain-killers did not affect the natural evolution of this headache after treatment with the infiltration of the GON, as all the patients who underwent infiltration showed a total improvement of their painful symptoms, without headache resulting from the withdrawal of pain-killers, nor did they show any pharmacological dependence. This is an evidence that the CH presents and organic etiology, not being influenced in its pathophysiology by the overuse of ergotamine derivatives.