The most important link in the chain is the patient, who benefits from the medication's action. Other actors in the drug supply chain include pharmaceutical companies, responsible for research, development, and production of medications; testing laboratories and research institutions, conducting studies and tests to validate medication safety and efficacy; regulators and government entities, overseeing and approving the launch of new medications into the market; distributors and wholesalers, responsible for delivering medications to various points of sale and healthcare; and finally, healthcare professionals such as doctors and pharmacists, who prescribe and dispense medications to patients. Each of these actors plays a vital role in ensuring medications reach those who need them safely and effectively.