Spring 2015, Issue 6 a Publication of the Department of Pharmacy, Norman Regional Health System
Total Page:16
File Type:pdf, Size:1020Kb
The Script The Script Spring 2015, Issue 6 A Publication of the Department of Pharmacy, Norman Regional Health System Vitamin K Route of Administration for Warfarin Reversal By Elizabeth Rathgeber, Pharm.D., Samantha Sepulveda, Pharm.D., Lysse Vadder, Pharm.D. In This Issue: Warfarin is an anticoagulant that works by inhibiting the synthesis of vitamin K-dependent clotting factors. Excessive anticoagulation can lead to an elevated international normalized ratio (INR), increasing the risk of bleeding complications. Vitamin K Route of Administration Phytonadione (vitamin K1) is used to reverse the effects of warfarin by promoting synthesis of for Reversal of Warfarin . 1 clotting factors. Vitamin K is available for several routes of administration: oral (PO), intravenous (IV), subcutaneous (SC), and intramuscular (IM). The low-dose (1 to 2.5 mg) PO formulation should The 2014-2015 NRHS be used in patients not requiring urgent reversal, which takes approximately 1.4 days for the INR to Pharmacy Residents . 2 reach less than 4.0 if the INR is between 6 and 10. Vitamin K 5 mg PO and 1 mg IV produce similar effects at twenty-four hours after administration.1 Higher doses of vitamin K can lead to warfarin Pharmacy and Therapeutics resistance and thrombosis. The IV route works more rapidly than PO or SC administration with INR Committee Update. 2 reduction beginning within 2 hours and full correction occurring within 24 hours. However, IV Humulin® R U-500 (Concentrated) administration has been associated with a small risk of anaphylactic reactions and is not 2 Added to NRHS Formulary . 3 recommended unless another route is not feasible and the increased risk involved is justified. The SC route is less effective and less predictable than oral and the intravenous formulations. Critical Medication Shortages . 3 Studies have shown less than 50% of patients with an INR greater than 4.0, but less than 10.0 will achieve an INR between 1.8 and 4.0 within 24 hours after SC administration of vitamin K.3 Prevention and Treatment of Intramuscular phytonadione administration is not recommended due to the risk of developing Extravasation . 4 hematomas. For this reason, SC administration is preferred over IM if parenteral therapy is required.4 Choosing the appropriate route of administration for vitamin K depends on several factors. While We welcome your thoughts, SC administration has been associated with less anaphylaxis, it has also shown less efficacy and comments and/or suggestions. predictability, when compared to IV vitamin K. Intravenous vitamin K has the quickest onset, but is associated with increased risk of anaphylaxis, thus should only be used if the risk is justified. Due to Do you have an idea for a story? Is there erratic absorption and risk for hematomas, IM administration of vitamin K should be avoided. Oral information we can provide you? is the preferred route of administration for non-urgent reversal of vitamin K antagonists due to its predictable pharmacokinetics according to the American College of Chest Physicians (ACCP) All correspondence concerning guidelines. The Script should be sent to: ACCP Recommendations for Vitamin K Administration5 INR Management Lisa Mayer, Pharm.D., BCPS 901 N Porter Ave., Box 1308 4.5 to 10.0, ! Hold warfarin Norman, OK 73070 without bleeding ! Recommend against routine use of vitamin K [email protected] ! Hold warfarin and give vitamin K PO (2 and 2.5 mg doses only studied > 10.0, and demonstrated low rates of major bleeding) without bleeding ! Allow 24-48 hours for INR reduction ! Hold warfarin and give vitamin K 5 to 10 mg IV Serious bleed, ! Administer Factor IX complex concentrate (four-factor PCC) any elevated INR ! May repeat vitamin K after 12 hours References 1. Ageno W, Gallus AS, Wittkowsky A, et al. Oral Anticoagulant Therapy. Antithrombotic Therapy and Prevention of Thrombosis, 9th ed. American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. CHEST 2012; 141(2)(Suppl):e44s–e88S. 2. Product information. Phytonadione Injectable Emulsion. So. El Monte, CA: Amphastar Pharmaceuticals Company, 2013. 3. Garcia DA, Crowther MA. Reversal of warfarin: case-based practice recommendations. Circulation 2012;125:2944-7. 4. Kearney TE. Vitamin K1 (phytonadione). In: Olson KR, ed. Poisoning and drug overdose. 6th ed. New York, NY: McGraw-Hill, 2012. www.accessmedicine.com. Accessed January 12, 2015. 5. Holbrook A, Schulman S, Witt DM, et al. Evidence-Based Management of Anticoagulant Therapy. Antithrombotic Therapy and Prevention of Thrombosis, (9th ed.) American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. CHEST Ansell J, Hirsh J, Hyle KE, et al. Oral Anticoagulant Therapy. Antithrombotic Therapy and Prevention of Thrombosis, 9th ed. American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. CHEST 2012; 141(2)(Suppl):e44s–e88S. Spring 2015, Issue 6 The Script The 2014-2015 NRHS Pharmacy Residents By Kim Whitley, Pharm.D. NRHS offers a year-long accredited Post Graduate Year 1 (PGY1) Pharmacy Residency that begins each year in July and ends in June of the following year. It allows pharmacists to accelerate their growth beyond entry-level competencies, to refine their clinical skills in a broad range of disease states and to provide evidence-based, patient-centered medication therapy. Residents are also cross-trained in distribution activities and can be found staffing at the HealthPlex on Monday through Thursday evenings. The Pharmacy department is proud to announce our pharmacy residents for the 2014-2015 year: Elizabeth Rathgeber, Samantha Sepulveda and Lysse Vadder. All three are 2014 graduates of The University of Oklahoma College of Pharmacy. Elizabeth Rathgeber was born in Alva, OK. Her current pharmacy interests include critical care, internal medicine, pediatrics, diabetes, and especially infectious diseases with a strong focus on HIV pharmacotherapy. After completion of her residency, Elizabeth plans to pursue a clinical pharmacy position in an inpatient setting. Samantha Sepulveda was born in Springfield, MO, raised in the Southwest United States, and moved to Oklahoma City, OK in 2009 from Southern Florida. Her pharmacy interests include internal medicine and infectious disease. She plans to pursue a clinical pharmacy position in a health system upon completion of her residency. Lysse Vadder was born in the town of Helena, located in Northwest Oklahoma. Her pharmacy interests include infectious diseases and gerontology/geriatrics. Upon completion of her residency, Lysse plans to be employed as a clinical pharmacist at Integris Bass Baptist in Enid, OK. She plans to obtain Board Certified Pharmacotherapy Specialist (BCPS) certification upon completion of her residency. Left to right: Elizabeth Rathgeber, Lysse Vadder, and Samantha Sepulveda Each resident undertakes a project during their residency, in which they present their research at local and national pharmacy conferences. Elizabeth’s project involves evaluating the appropriate use of Visipaque® and Omnipaque® in catheterization lab patients, taking into consideration their eGFR and procedure type. Lysse’s project involves reducing adverse drug events associated with opioid use by investigating the effectiveness of our existing protocols and evaluating the use of naloxone. Samantha’s project focuses on evaluation of anticoagulant reversal agents. Please take a moment to congratulate our residents as they conclude their residency! Pharmacy and Therapeutics Committee Update Dosage and Drug Indication Usual Dose P&T Action Strength 100 mg PO once daily prior to the first meal of the Canagliflozin Diabetes mellitus, type 2 - 100 and 300 mg day; may increase to 300 mg once daily (only in Added to formulary (Invokana®) adjunct therapy tablets patients with eGFR ≥60 mL/min/1.73m2) Treatment of diarrhea due Added to formulary – Fidaxomicin to Clostridium difficile 200 mg PO twice daily for 10 days 200 mg tablet restricted to GI and (Dificid®) (CDAD) ID physicians Fluticasone 100 Fluticasone/vilanterol One oral inhalation (fluticasone 100mcg/vilanterol mcg/vilanterol 25 COPD Added to formulary (Breo® Ellipta®) 25 mcg) once daily (maximum dose) mcg powder for inhalation Myelosuppressive Prefilled syringe of 5 mcg/kg/day SC; continue until anticipated nadir Tbo-filgrastim chemotherapy recipients 300 mcg/0.5 mL has passed and neutrophil count has recovered to Added to formulary (Granix®) with nonmyeloid and 480 mcg/0.8 normal range malignancies mL Added to formulary 200 mg tablet and Tedizolid Acute bacterial skin and with restrictions – 200 mg IV/PO once daily for 6 days 200 mg solution (Sivextro®) skin structure infections see Policy Addendum for reconstitution 40700-066.1 300 mg inhaled every 12 hours (do not administer 300 mg/5 mL Tobramycin inhaled Cystic fibrosis < 6 hours apart); administer in repeated cycles of 28 nebulization Added to formulary (Bethkis®) days on drug followed by 28 days off drug solution 2 Spring 2015, Issue 6 The Script Humulin® R U-500 (Concentrated) Added to NRHS Formulary U-500 (500 units/mL) regular insulin contains FIVE times as much insulin in 1 mL than standard U-100 (100 units/mL) regular insulin. It is useful in treating patients with insulin resistance (requiring doses of more than 200 units/day) because it allows for large doses of insulin to be given in smaller volumes and less frequently. The onset of action for U-500 regular insulin is 30 minutes, but because of its high concentration it has a l ong duration of action (up to 24 hours following a single subcutaneous dose). Based on its unique pharmacokinetic properties, U-500 regular insulin should be dosed with 2-3 injections per day and NEVER given intravenously. There are several safety issues that arise with the use of U-500 regular insulin. ! Its prolonged duration increases the risk for delayed secondary hypoglycemic reactions that may occur 18-24 hours after injection. ! There are no U-500 insulin syringes available; therefore, patients are usually instructed to take “XX unit marks on a U- 100 syringe” of U-500 regular insulin.