This document discusses coding technologies used to combat counterfeit pharmaceuticals. It describes overt coding methods like size, shape, and logos but notes these can be copied. Covert coding uses chemical or physical markers added invisibly. Regulatory barriers have hindered adoption of coding technologies but guidelines from the FDA have helped. Cost is also an issue, especially for generic drug makers. Future solutions may use nanotechnology and mobile phone verification to authenticate drugs for patients and ensure the correct personalized formulation.