BACKGROUND: Epistaxis is the most common symptom of hereditary hemorrhagic telangiectasia (HHT), affecting more than 98% of adults with HHT, with significant impact on quality of life. Floseal® has been shown to be effective for the management of anterior epistaxis, but has yet to be thoroughly evaluated in this population. Our goal was to evaluate the efficacy of Floseal® for managing acute anterior epistaxis in patients with HHT. METHODS: A pilot prospective clinical trial was conducted at two tertiary referral centres, St. Michael's Hospital, Toronto, Canada and The Ottawa Hospital, Ottawa, Canada. All patients with HHT presenting with acute anterior epistaxis to the two study centres, who enrolled in the study, received Floseal® treatment. The primary outcome measures were achievement of hemostasis and changes in the Epistaxis Severity Score (ESS) between baseline and one-month follow up. Secondary outcome measure included clinical assessment of the nasal cavity. RESULTS: Seven patients were included in the final analysis. All patients underwent treatment of anterior epistaxis with Floseal® and achieved control of epistaxis within 15-min post-application. Application of Floseal® was well tolerated, with patients reporting a pain score of 3 ± 3.13 out of 10. There was no statistically significant difference noted in ESS scores pre-treatment and one-month follow up, 6.27 ± 2.42 vs. 4.50 ± 2.44, p = 0.179. There was a significant improvement clinically on exam of the nasal cavity between baseline and at one-month follow up, indicated by a decrease in the clinical assessment score, 17.29 ± 7.70 vs. 9.57 ± 7.81 (p = 0.0088). CONCLUSIONS: Patients with HHT presenting with acute epistaxis were able to achieve hemostasis with one application of Floseal®, with the procedure being very well tolerated with minimal pain. Although there was no significant change in ESS scores, clinical assessment of the nasal cavity revealed significant improvement at one-month follow up post treatment with Floseal®. TRIAL REGISTRATION: This multi-centered prospective clinical trial was registered with ClinicalTrials.gov ( NCT02638012 ). Registered on December 22, 2015.