Overdose following administration of PRADAXA may lead to haemorrhagic complications due to its pharmacodynamic properties. Doses of PRADAXA beyond those recommended expose the patient to increased risk of bleeding.
In case of an overdose suspicion, coagulation tests can help to determine a bleeding risk (see Pharmacology: Pharmacokinetics under Actions and Precautions). A calibrated quantitative (dTT) test or repetitive dTT measureme nts allow prediction of the time by when certain dabigatran levels will be reached (see Pharmacology under Actions), also in case additional measures e.g. dialysis have been initiated.
Excessive anticoagulation may require discontinuation of PRADAXA.
In the event of haemorrhagic complications, treatment must be discontinued and the source of bleeding investigated. Since dabigatran is excreted predominantly by the renal route adequate diuresis must be maintained.
Depending on the clinical situation appropriate standard treatment, e.g. surgical haemostasis as indicated and blood volume replacement, should be undertaken.
For situations when rapid reversal is required the specific reversal agent (PRAXBIND, idarucizumab) antagonising the pharmacodynamics effect of PRADAXA is available. (See Precautions.)
In addition, consideration may be given to the use of fresh whole blood or fresh frozen plasma.
Coagulation factor concentrations (activated or non-activated) or recombinant Factor VIIa may be taken into account. There is some experimental evidence to support the role of these agents in reversing the anticoagulant effect of dabigatran but their usefulness in clinical settings has not yet been systematically demonstrated. Coagulation tests may become unreliable following administration of suggested reversing medicinal products. Consideration should also be given to administration of platelet concentrates in cases where thrombocytopenia is present or long acting antiplatelet drugs have been used. All symptomatic treatment has to be given according to the physician's judgement.
As protein binding is low, dabigatran is dialysable, however there is limited clinical experience in using dialysis in this setting (see Pharmacology: Pharmacokinetics under Actions).