OBJECTIVES: Models have previously focused on short-term costs and effectiveness measured in terms of intraocular (IOP) control. This model will assess the long-term effects of continued medical treatment in terms of glaucoma progression, low vision and quality-of-life. METHODS: A cost-utility analysis using a ten-year Markov model of first-line latanoprost, bimatoprost, travoprost or timolol, followed by second / third-line. Transition probabilities for this model were from a systematic review and mixed treatment comparison (MTC). Triggers for treatment switches included poor compliance (MTC); lack of IOP control (MTC); or progression of visual field defects (3 long-term clinical trials). Treatment dropouts were from expert opinion and death rates from UK national data. Follow-up times are from NHS treatment pathways, drug costs from UK Drug Tariff December 2007, cost of follow-up visits and surgery from NHS National Tariff 2007/8, and cost of low vision from a published UK national study. Utilities were from published sources. RESULTS: Patients were stable on treatment for 64%, 56%, 55% and 54% of follow-ups for latanoprost, bimatoprost, travoprost and timolol respectively. As a result, for every 1000 clinic appointments, 716 patients can be followed-up for a year if treated with latanoprost compared to 605 for bitmatoprost (similarly versus other strategies). The total cost of the latanoprost 1st line strategy is £6165, compared to £6239, £6238 and £6083 for bimatoprost, travoprost or timolol respectively (including surgery costs and cost of low vision), with 5.87, 5.85, 5.85 and 5.84 QALYs. The reduction in time spent with low vision for latanoprost is approximately 2 months compared to the other strategies. CONCLUSIONS:The model demonstrates that stablising a patient on treatment will lead to reduced disease progression and better outcomes in the long-term, and other benefits such as more efficient use of scheduled follow-up visits.