Purpose: Subconjunctival fibrosis is one of the main causes of failure of glaucoma filtration surgery. It can result in absence of a filtration bleb, a small scarred bleb, or a cystic bleb. 5-Fluorouracil (5-FU), mitomycin C (MMC), and topical steroids have been used to suppress subconjunctival fibrosis. Method: A study was done analyzing the number of postoperative subconjunctival 5-FU injections for trabeculectomy on pseudophakic eyes prior to and following the change to a BAK-free regimen. The cohort consisted of 16 consecutive cases undergoing primary trabeculectomy without intraoperative MMC or 5-FU. The trabeculectomy surgery included a groove sclerectomy procedure. Group A were 8 eyes of patients who had the author’s standard Chlorsig, Maxidex, and Prednefrin Forte eye drops tds. Group B were 8 eyes who had Chlorsig-dexamethasone and Optive-dexamethasone tds eye drops postoperatively. Results: Group B (BAK-free) patients required fewer postoperative 5-FU subconjunctival injections (average: 2.9, range: 1-5 injections) compared to Group A (BAK) patients (average: 7.3, range: 4-18 injections). This difference was statistically significant (P = 0.02, unpaired t-test). All patients had functioning blebs and did not require glaucoma medications to maintain target intraocular pressure. The Group B (BAK-free) patients had more diffuse blebs than the Group A (BAK) patients. Conclusion: The results demonstrated that when BAK was eliminated from postoperative eye drops in trabeculectomy, the number of postoperative 5-FU injections was reduced.