Patients with chronic daily headache with medication overuse are difficult to treat, especially when the doses of analgesia are substantial. We have previously shown that intravenous lignocaine (lidocaine) infusion is useful in maintaining pain control while the offending analgesic agent is withdrawn in these patients. The published data on long-term efficacy of this treatment is limited. We undertook a retrospective survey of 71 consecutive patients admitted for lignocaine infusion (mean 8.7 days) for treatment of chronic daily headache, with substantial analgesic abuse. Ninety percent of patients had a history of migraine headaches. In 80% of patients codeine was the predominant agent implicated in the analgesic rebound headaches (mean 1053 mg/week) and 24% used ergotamine-containing medications (mean 16 mg/week). Thirty-one percent frequently used injected narcotics. At completion 90% reported that their daily headache was absent or improved, and the analgesic agent was withdrawn successfully in 97%. At six month follow-up, 70% of patients reported that their daily headache was absent or improved and 72% of patients remained free of the offending analgesic agent. Intravenous lignocaine is a useful treatment in the management of chronic daily headache with substantial medication overuse. The benefits of the program last for at least six months.