Brief Answer:
Could be because of panadol

Detailed Answer:
Hello,

Thanks for posting on XXXXXXX

Looking at the two medications, they both can influence liver enzymes by increasing their blood levels.
Olanzapin can cause elevated alanine aminotransferase (ALT) levels but does not seem to influence other liver enzymes such as gamma GT. Where as, panadol (with active ingredient paracetamol or acetaminophen) is hepatotoxic or can cause liver failure especially when taken in high dose or in a situation of an already existing liver diseases. In a situation where you had a healthy liver or gall bladder, it is possible that paracetamol toxicity could be solely responsible for very high value of GGT.
But lets not rule out the fact that they are other numerous possible causes of increase GGT notably alcohol use, heart diseases, liver diseases, biliary tract diseases, use of some drugs such as barbiturates and phenytoin etc
There will also be the need to compare other liver enzymes such as AST, ALT, alkaline phosphatase etc to see if they are also elevated because paracetamol toxicity is always associated with elevation of AST and ALT.
GGT and alkaline phosphatase are more related to alcohol use and metabolic diseases.

Hope this helps and please feel free to write back for any follow-up queries.
Dr. Nsah
So yes, it is possible that the panadol you took may be responsible for increase gamma GT.

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