Omeprazole like similar proton pump inhibitors can deplete body Glutathione which stresses the liver .
( In Extreme cases of poisoning with some medications like Paracetamol N-Acetyl Cysteine is the antidote.)
If there is insufficient Organic Sulfur based Amino acids in your diet this liver stress with high enzyme levels can be a problem with Omeprazole but is not fatal on normal doses,
Good sources of Cysteine include Whey Protein.
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