Hepatic damage is very rare with Cymbalta...unless you have a history of prior liver disease:
"Hepatic
Cases of liver failure, including fatalities, have been reported. The majority of cases were reported in patients with past or current risk factors for liver injury, including alcohol abuse, hepatitis, or exposure to drugs with known adverse effects on the liver.[Ref]

Uncommon (0.1% to 1%): Acute liver injury, elevated liver enzymes (ALT, AST, GGT, alkaline phosphatase), hepatitis, increased blood bilirubin
Rare (less than 0.1%): Hepatic failure, jaundice[Ref]

Cymbalta:
"Hepatic
Common (1% to 10%): Increased alkaline phosphatase
Uncommon (0.1% to 1%): Increased ALT, GGT, and AST
Rare (less than 0.1%): Bilirubinemia, cholelithiasis, cholecystitis, hepatitis, jaundice
Frequency not reported: Abnormal liver function test
Postmarketing reports: Cholestatic hepatitis, hepatic necrosis[R"

Prozac
"Hepatic
Uncommon (0.1% to 1%): Abnormal liver function tests, cholelithiasis
Rare (less than 0.1%): Biliary pain, cholecystitis, hepatitis, idiosyncratic hepatitis, liver fatty deposits, transaminases increased, gamma glutamyltransferase increased
Frequency not reported: Abnormal hepatic function, aggravation of hepatic damage, cholestatic jaundice, hepatic failure/necrosis[Ref]"