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Chronic daily headache (CDH) still remains a relatively unexplored entity in our country. Misconceptions are common, unnecessary investigations are done often and inappropriate therapy is prescribed. Analgesic overuse in seldom recognized. The present report is a detailed analysis of CDH in an Indian setting. CDH has been defined as headaches occurring more than 15 days per month for more than 3 months (secondary causes excluded). Over two years (1998-99) 876 cases (51.2% of all primary headaches) were seen. More than one year follow up data ware available in 232 subjects (m-52; F-180). The distribution of these cases were as follows: a) Chronic tension type headache (CTH) : 24(10.3%); (b) transformed migraine (TM) : 166(17.6%); (c) migraine-CTH-from episodic tension headache : 12 (5.2%); (d) new persistent CDH : 3 (1.3%); and (e) chronic post-traumatic headache : 27 (11.6%). There were 166 cases of TM (M:F-1:4.7; age 26-58 yrs.). History of past episodic migraine was present in all. Transformation had been gradual (89.2%) or acute (10.8%). Possible factors in transformation included - psychological stress (43.8%), analgesic overuse (20.9%), ergot overuse (4.2%). Hormone replacement therapy seemed to be implicated in 3 female subjects. Analgesic overuse was limited between intake of 600-2400 mg of aspirin equivalent per day (mean 735 mg). Ergot overuse varied between 1-3 mg/day of ergotamine for 3 or more days per week. With medical therapy approximately 70% TM and 40% CTH patients noted significant improvement. About 80% of these relapsed on therapy withdrawal. CDH in India is not uncommon. Analgesic/ergot overuse needs to be recognized early. The average dose of analgesic implicated in CDH seems much less compared to that reported from the West.