Background: Anticoagulants are extensively used in the in-patient setting for the prevention and treatment of venous thromboembolism (VTE) and stroke prevention for Atrial Fibrillation. They are high-risk medications associated with a significant rate of medication errors among hospitalized patients. The Pharmacy Department in collaboration with Medical Department in Hospital Tengku Ampuan Afzan (HTAA) is seeking to expand anticoagulation services and standardize care by implementing an In-Patient Anticoagulation Service (IPACs) providing daily surveillance and dosing consultation for patients receiving anticoagulant therapy (ACT). The team comprises of consultant hematologist, pharmacists, general physician and medical officers. The objectives of this study are to describe the implementation and outcomes of an IPACs and identifying the issues in the management of ACT. The use of anticoagulant was retrospectively collected from IPACs data during the period February 2017 to December 2018. Results: 320 patients were referred to IPAC, with 59% of them were female. Of 303 patients seen by IPACs team, 52.5% patients used for acute VTE, 19.5% were referred for anticoagulant reversal and 3.3% for recurrent VTE. Almost two-third (72.3%) of patients used warfarin followed by 20.5% used direct oral anticoagulant and 7.2% used either low molecular weight or heparin. Of 159 patients referred for acute VTE, only 33% of them received VTE prophylaxis. Issues that were identified were the inappropriate dose of Vitamin K for over-warfarinization and underutilisation of prothrombin complex concentrate in the setting of prolonged international normalized ratio (INR) with severe bleeding as well as doing daily INR leading to improper titration of warfarin. Unsupervised and improper dose of heparin infusion and patients discharged with longer appointment for INR monitoring are the main issues encountered in IPACs. Conclusion: With the IPACs, the awareness of VTE prophylaxis and the issues that related to ACT were resolved. This service appears to enhance quality of patient care in ACT.