However , carnitine supplementation at dosages of ≤ 1000 mg/day ( p = 0.035 ) or equal to 2000 mg/day ( p = 0.013 ) result ed in significant reduction in ALT level , while doses more than 2000 mg/day did not change ALT  significantly .
Carnitine exerts its reducing effect on serum ALT and AST levels only when these aminotransferases are raised or when the duration of supplementation lasts at least 3 months .
Results of the current meta- analysis showed that carnitine supplementation can decrease serum AST and ALT levels significantly , especially when supplementation lasts 3 months or more in patients with elevated serum aminotransferase levels
Effects of carnitine on peripheral blood mitochondrial DNA copy number and liver function in non-alcoholic fatty liver disease.
BACKGROUND / AIMS Functional and anatomical abnormalities of mitochondria play an important role in developing steatohepatitis . Carnitine is essential for enhanced mitochondrial beta oxidation through the transfer of long-chain fatty acids into the mitochondria . We examined the impact of carnitine complex on liver function and peripheral blood mitochondria copy number in NAFLD patients . METHODS Forty-five NAFLD patients were enrolled . Patients were categorized into the carnitine complex-administered group and control group . Before and 3 months after drug administration , a liver function test and peripheral blood mitochondrial DNA and 8-oxo-dG quantitive analysis were conducted . RESULTS In carnitine treatment group , ALT , AST , and total bilirubin were reduced after medication . There was no difference in AST , ALT , and total bilirubin between before and after treatment in control group . In carnitine group , peripheral mitochondrial DNA copy number was significantly increased from 158.8+/-69.5 copy to 241.6+/-180.6 copy ( p=0.025 ) . While in control group the mitochondrial copy number was slightly reduced from 205.5+/-142.3 to 150.0+/-109.7 . 8-oxo-dG level was also tended to decrease in carnitine group ( p=0.23 ) and tended to increase in control group ( p=0.07 ) . CONCLUSIONS In NAFLD , the carnitine improved liver profile and peripheral blood mitochondrial DNA copy number . This results suggest that carnitine activate the mitochondria , thereby contributing to the improvement of NAFLD
However , carnitine supplementation at dosages of ≤ 1000 mg/day ( p = 0.035 ) or equal to 2000 mg/day ( p = 0.013 ) result ed in significant reduction in ALT level , while doses more than 2000 mg/day did not change ALT  significantly .
Carnitine exerts its reducing effect on serum ALT and AST levels only when these aminotransferases are raised or when the duration of supplementation lasts at least 3 months .
Results of the current meta- analysis showed that carnitine supplementation can decrease serum AST and ALT levels significantly , especially when supplementation lasts 3 months or more in patients with elevated serum aminotransferase levels