OBJECTIVE: To estimate the medical outcome of glaucoma /ocular hypertension (OH) treatment in France according to usual practice. METHODS: Ophthalmologists selected at random had to include 4 consecutive patients older than 18 seen in consultation during a week, 2 with glaucoma and 2 with OH. Socio-demographics, general and eye comorbidities, glaucoma risk factors, visual acuity (VA), papilla, and visual fields were collected. A visual field defect (VFD) was defined as a deterioration of papilla exam and visual field since diagnosis. A treatment switch was defined as adding a new drug or changing any of the current treatments. Time to failure of a treatment regimen, broken out by the number of treatment switches, was compared using the likelihood ratio applied to survival curves. RESULTS: One hundred and twenty seven of the 337 patients included by the 84 ophthalmologists had their full treatment documented from diagnosis. Twelve patients developed a new VFD after diagnosis (average follow-up: 2.5 years). No statistically significant difference on the known confounding factors of VFD was found between patients with and without VFD. Patients with VFD had a lower VA (-1.23; P<0.08). At 3 years, 2.7% of the patients with no treatment switch had a VFD, compared to 22.6% with one treatment switch and 46.3% with >2 treatment switches. The difference between the three groups was statistically significant (P<0.01). CONCLUSION: Patients with fewer treatment switches have less VFD. Under isotropic hypotheses, effective treatment strategies should be used first line in order to avoid visual field defect and therefore protect long-term patient vision.