Medication-Overuse Headache: clinical and therapeutic problems

The interactions between chronic headache and medication overuse are complex and not yet fully clarified. In particular, the mechanisms by which medication overuse takes part in the chronicization process are still object of hypotheses. Certainly, medication overuse complicates the therapeutic approaches to chronic headache. Medication overuse hampers the effect of prophylactic therapies, and only the interruption of the overuse, over a variable period of time, leads to the disappearance, or at least the reduction in the frequency of headache. Only at that point it is possible to start the prophylactic treatment with a wellfounded probability of success. Unfortunately, interrupting medication overuse is not an easy task, due to both the severity of the pain symptomatology and to rebound headache which can compel the patient to resume medication. Objectives The aim of our research was to analyze patients with medication- overuse headache, with respect to the characteristics of drug medication behaviour and its consequences for headache treatment. Patients and methods We studied a consecutive series of 50 patients, newly admitted to the in-patient service of the Headache Centre of the University of Modena and Reggio Emilia. Data were collected by means of a questionnaire, specifically prepared for this study, recorded into a specific database and analysed by SPSS 6.1.2 program, version for Windows 98. Results The combination of indomethacin plus caffeine plus prochlorperazine, and triptans were the medications most frequently overused by our patients; only a few patients overused ergot preparations. The majority of patients used the same type of drug daily. All patients referred they increased the frequency of self-medication because the headaches were getting worse. For most patients medication overuse made the headache more endurable, thus allowing them to work or function more or less normally in daily life. Only a minority experienced withdrawal symptoms after discontinuation of the medication overuse. After detoxification, antidepressants were the class of drugs most used for prophylaxis. Discussion During chronic use of a medication indicated for acute treatment of headache, the therapeutic results do not derive solely from the drug but also from the organism’s adaptation to the repeated use. This time-process of compensatory adjustments might partly explain both the chronicization of headache and the withdrawal symptoms when medication overuse is interrupted. Conclusion Medication-overuse headache should be prevented because its management is very difficult. It is necessary to address, at the same time, both the chronic pain condition and the medication overuse.