Accidental Rivaroxaban Intoxication in a Boy: Some Lessons in Managing New Oral Anticoagulants in Children.

Novel oral anticoagulants offer equivalent or improved therapeutic profiles compared with warfarin, with less risk of bleeding, no interactions with food, and no need for routine laboratory monitoring. Caution must be exercised in using these drugs in certain patient populations, for example, renal insufficiency, those receiving additional antithrombotic therapy, those with questionable compliance, children, and those with a high risk of gastrointestinal bleeding. One of the novel oral anticoagulants, rivaroxaban, is a direct Factor Xa inhibitor, used to reduce risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, deep vein thrombosis, and pulmonary embolism. We report a child who presented abnormal coagulation tests after unintended ingestion of 4 tablets of rivaroxaban. The patient was treated with fresh frozen plasma as well as admitted to intensive care and improved several hours later. We discuss his presentation and review of the literature on this topic.

Massive intoxication with rivaroxaban, phenprocoumon, and diclofenac: A case report.

RATIONALE: Oral anticoagulants and painkillers, some with an additional effect on the coagulation system, are widely used and are therefore prone to abuse and (intentional) overdose. We report the case of a patient with a massive mixed anticoagulant intoxication. PATIENT CONCERNS: The patient had ingested 1960 mg rivaroxaban, 31.5 mg phenprocoumon, 1425 mg diclofenac, and 21,000 mg metamizole in suicidal intention. DIAGNOSES: Massive mixed anticoagulant overdose. INTERVENTIONS: The patient was closely monitored. The phenprocoumon overdose was treated by the administration of vitamin K and PCC. OUTCOMES: Despite the massive inhibition of the coagulation system, the patient did not experience bleeding apart from a slight gross hematuria. LESSONS: Despite the ingestion of a massive amount of rivaroxaban, the plasma levels were not as high as feared, due to the ceiling effect of rivaroxaban absorption. Elimination occurred according to the half-life of rivaroxaban and was not unduly prolonged by the ingested quantity.

Lack of significant bleeding despite large acute rivaroxaban overdose confirmed with whole blood concentrations.

BACKGROUND: Since intentional overdose with rivaroxaban is expected to lead to significant coagulopathy and bleeding, prophylactic reversal has been suggested. We report a single massive ingestion confirmed by a blood concentration that was managed with expectant therapy alone. CASE REPORT: A 71-year-old man with atrial fibrillation, aortic valve replacement, and congestive heart failure presented to the emergency department after an intentional ingestion of 97 (1940 mg total) rivaroxaban tablets in a suicide attempt. Initial laboratories revealed: PT, 60.2 s; INR 7.2; aPTT, 55.7 s; BUN 28 mg/dL; and creatinine 1.2 mg/dL. A whole-blood rivaroxaban concentration obtained on hospital-day three was 160 ng/mL. The patient was admitted for continued observation and the coagulation markers trended downward with no major bleeding events. No reversal agents or blood products were given during his hospitalization. CONCLUSION: In the setting of a single, acute rivaroxaban overdose, with normal renal function, and no active bleeding, conservative therapy alone may be sufficient.

An Observational Study of the Factor Xa Inhibitors Rivaroxaban and Apixaban as Reported to Eight Poison Centers.

STUDY OBJECTIVE: Rivaroxaban and apixaban are part of a new group of oral anticoagulants targeting factor Xa and approved by the Food and Drug Administration in 2011 and 2012. These oral anticoagulants are administered at fixed daily doses, without the need for laboratory-guided adjustments. There are limited data available on supratherapeutic doses or overdose of the oral Xa inhibitors. This study characterizes the clinical effect in patients exposed to rivaroxaban and apixaban. METHODS: A retrospective study collected data from 8 regional poison centers covering 9 states. Cases were initially identified by a search of the poison centers' databases for case mentions involving a human exposure to Xarelto, rivaroxaban, Eliquis, or apixaban. Inclusion criteria included single-substance exposure. Exclusion criteria were animal exposure, polysubstance exposure, or information call. Data for the study were collected by individual chart review, including case narratives, and compiled into a single data set. RESULTS: There were 223 patients: 124 (56%) were female patients, mean age was 60 years, and 20 were children younger than 12 years (9%). One hundred ninety-eight patients ingested rivaroxaban (89%) and 25 ingested apixaban (11%). Dose was reported in 182 rivaroxaban patients, with a mean dose of 64.5 mg (range 15 to 1,200 mg), and in 21 apixaban patients, with a mean dose of 9.6 mg (range 2.5 to 20 mg). For rivaroxaban, prothrombin time was measured in 49 patients (25%) and elevated in 7; partial thromboplastin time, measured in 49 (25%) and elevated in 5; and international normalized ratio, measured in 61 (31%) and elevated in 13. For apixaban, prothrombin time was measured in 6 patients (24%) and elevated in none; partial thromboplastin time, measure in 6 (24%) and elevated in none; and international normalized ratio, measured in 5 patients (20%) and elevated in none. Bleeding was reported in 15 patients (7%): 11 rivaroxaban and 4 apixaban. The site of bleeding was gastrointestinal (8), oral (2), nose (1), bruising (1), urine (1), and subdural (1). The subdural bleeding occurred after fall and head injury. All cases with bleeding involved long-term ingestions. Coagulation test results were normal in most patients with bleeding: prothrombin time 5 of 6 (83%), partial thromboplastin time 5 of 6 (83%), and international normalized ratio 5 of 9 (55%). Blood products were used in 7 rivaroxaban patients (1 suicide) and 3 apixaban patients. No bleeding or altered coagulation test results occurred in children, which all involved a one-time ingestion. All 12 suicide attempts involved rivaroxaban: altered coagulation test results occurred for 5 patients (42%), no bleeding occurred in any suicide attempt patient, 1 patient was treated with fresh frozen plasma (international normalized ratio 12.47), and dose by patient history did not predict risk of altered coagulation or bleeding. Two rivaroxaban patients experienced elevation of hepatic transaminase levels greater than 1,000 U/L. CONCLUSION: Bleeding after Xa inhibitor ingestion as a single agent is uncommon. Prothrombin time, partial thromboplastin time, or international normalized ratio may be elevated in a minority of cases but appears unreliable to measure risk of bleeding. Massive acute ingestion in suicide attempt may result in significant anticoagulation. Single exploratory ingestion by children was not associated with toxicity.