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Decreased INR after acenocoumarol, ombitasvir/paritaprevir/ritonavir and dasabuvir co-administration
A de Lorenzo-Pinto1, Á Giménez-Manzorro1, C G Rodríguez-González1
1Pharmacy Department, Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.
What Is Known And Objective:
Limited data are available on co-administration of acenocoumarol with direct-acting antiviral agents for chronic hepatitis C virus infection.
Case Summary:
We report a case of a patient who required a significant increase in acenocoumarol weekly dose probably due to an interaction with ombitasvir/paritaprevir/ritonavir and/or dasabuvir. A causality assessment of the drug-drug interaction leading to a reduced INR was conducted according to the Naranjo algorithm. A score of 6 suggested that the adverse drug reaction was probable.
What Is New And Conclusion:
Because of possible INR abnormalities during the concomitant use of acenocoumarol, ombitasvir/paritaprevir/ritonavir and dasabuvir, clinicians should closely monitor INR values.
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