The purpose of this study was to examine the effects of genetic and non-genetic variables on the variability of stable warfarin dosages in South Indian patients. Method: The study included 96 participants who had consistent warfarin dosages. A few instances of the clinical and demographic data that was captured were age, BMI, and warfarin indications. Single nucleotide polymorphisms in the CYP2C9*2 and CYP2C9*3 genes were discovered in gDNA utilizing the Biorad MJ Mini TM thermocycler. Results: The daily doses of warfarin needed by individuals with variant CYP2C9*2,*3 genotypes were considerably lower than those of patients with wild-type genotypes. The genotype frequencies for CYP2C9*2 and CYP2C9*3 were 64.6%, 19.8%, and 15.6% for the CC, CT, and TT genotypes, and 39.6%, 39.6%, and 20.8% for the AA, AC, and CC genotypes, respectively. The daily recommended dose of warfarin in patients with homozygous wild-type genotype for CYP2C9 (*1/*1) was (4.07± 1.75 mg), which was noticeably better than the daily recommended doses in patients with *1/*2, *1/*3, and *2/*2, *2/*3, and *3/*3 (1.54 ±1.05 mg, p < 0.001). Conclusion: Warfarin dosage is influenced by both genetic and non-genetic factors. Warfarin dosage may be impacted by both genetic and non-genetic factors, which play a significant role. Individual differences in warfarin dosage are demonstrated by CYP2C9*2 and CYP2C9*3 polymorphisms, as well as by age and body mass index.