CYP4F12 is a cytochrome P450 monooxygenase primarily involved in metabolizing endogenous polyunsaturated fatty acids (PUFAs). The enzyme catalyzes hydroxylation and epoxidation of fatty acids, particularly arachidonic acid to 18-hydroxyarachidonic acid, with omega-2 position preference 1. CYP4F12 exhibits low activity toward leukotriene B4 but notably high catalytic activity toward the antihistamine ebastine 2, suggesting a distinct substrate specificity from other CYP4F isoforms that emphasizes xenobiotic metabolism in the small intestine and liver 2. Both CYP2J2 and CYP4F12 contribute to intestinal ebastine hydroxylation, though CYP2J2 is predominant 3. Genetic polymorphisms in CYP4F12 affect enzyme expression and catalytic activity; variants Val90Ile and Arg188Cys show significant functional changes 4. Disease relevance includes associations with glioma susceptibility (rs688755 variant) 5 and head and neck squamous cell carcinoma, where CYP4F12 downregulation promotes cell migration through epithelial-mesenchymal transition 6. Additionally, CYP4F12 enhances hepatitis C virus replication through direct interaction with viral nonstructural protein 5B 7. The clinical significance remains limited regarding warfarin dosing, where CYP4F12 polymorphisms show minimal pharmacogenetic impact 8.