{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T16:03:03Z","timestamp":1785168183619,"version":"3.55.0"},"reference-count":41,"publisher":"Oxford University Press (OUP)","issue":"15","license":[{"start":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T00:00:00Z","timestamp":1773187200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,7,22]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>The purpose of this report is to highlight a case of utilizing weight-based enoxaparin for prophylaxis of venous thromboembolism (VTE) in an elderly, extremely underweight patient. VTE represents a significant concern for hospitalized patients. There is a dearth of literature regarding utilization of low-molecular-weight heparins such as enoxaparin or unfractionated heparin in patients who are underweight.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Summary<\/jats:title>\n                    <jats:p>In this case, a 68-year-old female who was extremely underweight (21.8 kg) presented to the emergency department in acute respiratory distress secondary to pneumonia and a chronic obstructive pulmonary disease exacerbation. The patient had a Padua score of 5 and an IMPROVE score of 2 that signified the necessity of pharmacologic VTE prophylaxis. A clinical decision was made to utilize a weight-based enoxaparin dosing strategy for VTE prophylaxis using a pediatric dilution to deliver the dose. Enoxaparin was initiated at 0.5 mg\/kg (10 mg) subcutaneously daily and monitored via anti\u2013factor Xa peak levels to verify that the dose provided an adequate prophylactic level. Ultimately, a dose of 0.5 mg\/kg resulted in an appropriate anti\u2013factor Xa level of 0.21 units\/mL, equating to suitable VTE prophylaxis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>A review of the literature revealed little evidence for optimal anticoagulation dosing for VTE prophylaxis in adult patients weighing under 40 kg. Various adjustment strategies have been utilized; however, there is no available evidence pertaining to patients at the extreme of low weight represented by the reported case or to attainment of an anti-factor Xa level within the therapeutic range in such patients. This case represents the use of a weight-based enoxaparin strategy for an extremely underweight elderly patient and the attainment of a therapeutic prophylactic anti\u2013factor Xa level.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ajhp\/zxag080","type":"journal-article","created":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T12:31:25Z","timestamp":1772973085000},"page":"e549-e555","source":"Crossref","is-referenced-by-count":0,"title":["Use of weight-based dosing of enoxaparin for venous thromboembolism prophylaxis in an extremely underweight elderly patient"],"prefix":"10.1093","volume":"83","author":[{"given":"Cameron","family":"Lanier","sequence":"first","affiliation":[{"name":"Ballad Health at Johnson City Medical Center , Johnson City, TN ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Molly","family":"Lassiter","sequence":"additional","affiliation":[{"name":"Ballad Health Corporate Pharmacy , Johnson City, TN 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