Our results show that the pharmacogenetics of CYP2D6 (*2 rs16947; *35 rs769258; *4 rs3892097; *9 rs5030656; and *41 rs28371725), ADRB2 (rs1042714), and PTGFR (rs3766355 and rs3753380) have an impact on individuals’ responses to glaucoma treatment involving beta-blockers, prostaglandin analogues, or prostamides, respectively. The gene discussed is ADRB2; the disease is glaucoma.