Can levothyroxine cause an increase in liver enzymes?

Dear Ask The Doctor: High liver enzymes started at 120 in may 2011 had several lab test all came back negative even all hepatitis test also an ercp test was done test negative had gallbladder removed five years ago. Had recent lab test in June 2011 test came back 141 liver enzymes... Why?

Elevation of liver enzymes could mean a lot of things. It is an indicator of liver cell injury but can also be encountered in other cases. ALT and AST are the usual liver enzymes used as a tool to assess liver cell injury. Elevations of these enzymes are common especially in those who drink alcohol regularly. Some drugs (aspirin, cholesterol-lowering drugs) can also cause elevations of liver enzymes. Even herbal meds and/or drinks can cause elevated liver enzymes. Values up to 300 iU/L are very non-specific and usually ignored because it does not denote serious liver injury; it’s only trivial, reversible and values can go back to normal once the offending agent is stopped. If it exceeds 300 iU/L further investigations may be necessary. In your case, it could be due to the thyroid drugs you are taking and continuous monitoring of your liver enzymes, perhaps every 6-12 months would suffice. Serious liver conditions have been ruled out since hepatitis blood tests were done already and turned out normal. I do hope I have appeased your concerns and take care always.