Objectives: To study the effect of metformin on serum glucose and some liver function tests
including serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate
aminotransferase (AST) and bilirubin in type 2 diabetic patients.
Design: Case-control study.
Setting: The study was carried out in Al-Waffa centre for diabetes in Mosul, during the period
from March 2004 to December 2004.
Participants: Fifty type 2 diabetic patients treated with metformin were included. In addition,
two control groups were used, 50 nontreated diabetic patients and 50 apparently healthy
Results: Serum glucose in metformin treated diabetics -was lower (P<0.05) than the nontreated
diabetics; however, ALP and ALT were higher (P<0.05) in the treated diabetics. At the same
time, AST and bilirubin did not change by metformin by using Duncan test.
Conclusion: Metformin causes increase in some liver function tests. Therefore, patients treated
with metformin should be periodically examined for the liver function tests.