One hundred and one patients suffering from chronic daily headache (CDH) and medication overuse were treated, in an in-patient setting, with abrupt discontinuation of the medication overused, intravenous hydrating, and intravenous administration of benzodiazepines and ademetionine. The mean time to CDH resolution was 8.8 days. The in-patient withdrawal protocol used was effective, safe and well tolerated. There was a trend for a shorter time to CDH resolution in patients who overused triptans (P = 0.062). There was no correlation between time to CDH resolution and either the type of initial primary headache or duration of medication abuse, whereas time to CDH resolution was related to daily drug intake (P = 0.01). In multiple regression analysis, daily drug intake, age and type of medication overused were independent predictors of time to CDH resolution. At 3-months' follow-up, no patient had relapsed and was again overusing symptomatic medications.