DOACS IN OBESE PATIENTS

        -As noted by Pharmacy, use of DOACs in obese patients are currently
        being studied, and the lastest 2016 guidelines from the ISTH (Martin, K
        et al "Use of the direct oral anticoagulants in obese patients:guidance
        from the SSC of the ISTH" Journal of thrombosis and hemostasis Volume
        14, Issue 6 June 2016 Pages 1308-1313) - that in patients with BMI > 40
        kg/m2 or a weight of > 120 kg (which is 264 lbs), DOACs should not be
        used because "...there are limited clinical data available for
        patients at the extreme of weight, and the available PK/PD evidence
        suggests that decreased drug exposures, reduced peak concentrations and
        shorter half-lives occur with increasing weight, which raises concerns
        about underdosing in the population at the extreme of weight."
                -His BMI = 37.8
        -These guidelines also state "If DOACs are used in a patient with a BMI
        of > 40 kg m-2 or a weight of > 120 kg, we suggest checking a drug-
        specific peak and trough level (anti-FXa for apixaban, edoxaban, and
        rivaroxaban; ecarin time or dilute thrombin time with appropriate
        calibrators for dabigatran; or mass spectrometry drug level for any
        of the DOACs). If the level falls within the expected range,
        continuation of the DOAC seems reasonable. However, if the drug-
        specific level is found to be below the expected range, we suggest
        changing to a VKA rather than adjusting the dose of the DOAC"
                -http://onlinelibrary.wiley.com/doi/10.1111/jth.13323/full