This will be an open-label, clinical study in male and female patients with NASH (n=10) and healthy volunteers (n=10) of any race and ethnicity investigating the effect of liver disease on the pharmacokinetics of 99mTechnetium-mebrofenin. The use of the gamma emitter 99m Tc- labeled mebrofenin will allow real-time assessment of hepatic exposure. To determine the differences between healthy subjects and patients with NASH, blood and hepatic concentrations will be analyzed by non-compartmental analysis. Additionally, serum bile acid samples and fibroscan data will be collected to determine whether the bile acid profile and/or fibroscan readings are different between healthy subjects and patients with NASH. Changes in 99mTc-mebrofenin will be correlated with the patient specific bile acid profile and fibroscan data. This study will increase our understating of the effect of liver disease on the disposition of medications that undergo transporter-mediated hepatic clearance.