high SGPT

Dear ,

I have had a blood test and noticed that i have a high rate of sgpt , so my doctor asked me to do some other test like :
- hepatitis a,b , c : all of them were negative
- ultrasound imaging of the liver : everything was normal
- some other test like iron , vitamines , cholesterol , triglyceride... everything was normal just my ferritin elisa was a little hight.

my question is , why was the SGPT rate high in my blood ?
i heard some medicines affect the rate , is it true? if it is , note that i had fever and dhiarea before doing the test and i was taking antibiotic medicines and tylenol and panadol .

thank you