Abstract Purpose To report the outcome of 5-fluorouracil (5-FU)–augmented bleb needling revision of failed and failing filtration blebs and to identify risk factors for failure, indicators for success, and any complications of the procedure. Design Prospective, observational, noncomparative, interventional case series with survival analysis. Methods The results of 101 bleb needling procedures augmented with subconjunctival 5-FU injection were determined after a minimum follow-up of 9 months. Kaplan–Meier plots were constructed and a Cox proportional hazards regression analysis was performed to assess the association between study factors and time to failure. Main outcome measures Reduction in intraocular pressure (IOP) by 2 criteria (<22 mmHg, >30%), glaucoma medications, complications, and factors associated with outcome. Results At the time of their last follow-up visit, 60 eyes had an IOP <22 mmHg, mean IOP being reduced from 26.5 mmHg to 18 mmHg after a median of 1 needling procedure (mean, 1.6). The median interval between the “index” filtration surgery and the first (or only) needling procedure was 3.1 months, with a range of 10 days to 11 years. There was a reduction in mean number of topical antiglaucoma agents from 0.7 to 0.2 per successful eye and a median follow-up duration of 18.7 months (range, 9.3–52.0 months). Thus, the overall cross-sectional success rate of the procedure at the time of the last visit was 59.4%. Strong evidence was found for an association between the immediate attainment of a low IOP (<11 mmHg) and longer survival times. None of the other proposed factors that may have affected outcome were identified as having a statistically significant effect; however, this may have been the result of the low statistical power for some of the factors in this study. Conclusions These data suggest that bleb needling augmented with 5-FU is a safe and effective method by which a significant number of failed or failing filtration blebs can be rescued from failure. Attaining an immediate reduction in IOP to <11 mmHg seems to be a favorable factor with respect to reasonably long-term efficacy.