Abstract Disclosure: M.D. Lundholm: None. P.P. Rao: None. Objective: It is thought that anticoagulant (AC) or antiplatelet (AP) therapy at the time of thyroid nodule fine needle aspiration biopsy (TNFNAB) may increase the risk of non-diagnostic results and post-procedure hematomas. However, interrupting a patient’s AC or AP can lead to procedural delays or have thrombotic consequences. Since there is currently no consensus on whether or not to hold these medications, this study aims to survey the expertise of our providers across multiple specialties. Methods: A survey was sent out to Cleveland Clinic providers who have performed TNFNABs for patients with an active prescription for AC or AP since 2010. Providers were asked if they routinely held a number of blood thinner medication classes and included a free response section for open-ended comments. Results: The survey responses represented 60 providers (of 68 invited, 88% response rate). Respondents were 51.7% medical endocrinologists, 30% interventional radiologists, 13% surgical endocrinologists, and 5% ENTs. Of respondents, 13.3% held aspirin 81 mg, 15.0% held aspirin 325 mg, 41.7% held other antiplatelet agents, 73.3% held warfarin, 43.3% held direct oral anticoagulants (DOACs), and 43.3% held heparin. No department was uniform in practice, with the least agreement (responses closest to 50%) amongst medical endocrinologists. In a subset of 15 providers who have performed ≥100 TNFNABs on patients with AC/AP, a consensus emerged not to hold aspirin at any dose, but there was no agreement in any other AC/AP categories (hold rates ranging 53.5-66.6%). Free response themes reiterated that the main concerns for continuing blood thinners are hematomas and non-diagnostic results. Other comments included consideration of the nodule features such as location as well as strategies used to lower risk for hematomas (i.e., small-gauge needles, ice, holding pressure). A couple responses referred to the Society of Interventional Radiology (SIR) and the International Society on Thrombosis and Haemostasis (ISTH) guidelines which offer INR and platelet goal recommendations prior to any procedure with a low bleeding risk. Discussion: A survey of Cleveland Clinic providers demonstrated that ≥85% continue aspirin therapies prior to TNFNAB. However, there is no such agreement in any other category of AC/AP medication, even amongst the most experienced providers. The closest guidelines available come from SIR and ISTH and rely on recent platelet and/or INR information, which may not be available in routine endocrinology practice. The caveat is that these recommendations are not specific to TNFNAB and do not take into account the nuances of this procedure. Conclusion: There is wide variation in provider opinions and practice patterns regarding AC and AP medications prior to TNFNAB. This highlights the need for further study into the safety and adequacy of TNFNAB performed on uninterrupted AC or AP therapy. Presentation: 6/3/2024