Nicotine replacement therapy (NRT) has been available free of charge for medical cardholders in Ireland (29.84% of the population) since April 2001. We investigate the prescribing patterns for NRT before and after this change in reimbursement status. Using the General Medical Services Payments Board prescription database we conducted a detailed analysis of NRT prescribing (ATC code N07BA) for those patients eligible for free medications (1,168,745 patients) in all health board areas in Ireland from January to December 2002. We determined the number of monthly prescriptions for each NRT preparation (ATC code N07BA01) and bupropion (ACT code N07BA02) together with total expenditure. The mean dosage, duration of therapy and age/gender distribution of NRT treatment was also obtained. We identified 49,826 patients who received smoking cessation products in 2002. Of these 94.6% (47,147 patients) were prescribed NRT, the remaining 5.4% (2,679 patients) received bupropion. Nicotine patch therapy accounted for 82.8% of all NRT dispensed. Prescribing trends for NRT show the number of patients receiving such therapy is greatest in January and February with expenditure highest in the first quarter. Prescribing of NRT is greatest amongst the 25-54 year age group with peak prescribing between the ages of 35-44 years. The highest dose of nicotine patch therapy (15-21 mg/day) was prescribed for the majority (73%) of patients. Over three quarters (75.6%) of all patients were prescribed nicotine patch therapy for a period of less than or equal to 4 weeks (48.1% less than or equal to 2 weeks). Similarly for nicotine gum where 77% of all patients received just one month of therapy. This analysis indicates quality NRT prescribing in the primary care setting. The dose and duration of therapy is in keeping with recent NICE guidance indicating that the NRT expenditure of 2,709,954 euros in 2002 should provide value for money.