Hi, My Dermatologist Asked Me To Do Some Liver Test

Hi, my dermatologist asked me to do some liver test in order to prescribe reucotane to treat my acn, my GGT level came out to be 86, I'm a female 40 years old &I stopped drinking alcohol 1 year prior to the test, I did an ultra sound and it came out normal except for a sebaceous cyst, my dr told me there's nothing to worry about, is this the case? Is there any tests I should do? How can I lower my GGT? My body weight is 53 kg / 157 cm