Before 2006, the medicine carrying requirements was under ILO R105 : Ship's medicine chest recommendations.

In 2006, the ILO MLC was adopted by a special ILO conference. The purpose was to consolidate all the ILO requirements related to seafarers as one document.

MLC Section B, part 4.1.3 has the requirement for the flag states regarding the requirement of medicine chest on board. 

The flags that have ratified the MLC convention must adopt to this requirement as per Maritime Labour convention (MLC). The flags that have not ratified the MLC convention will have their own rules under their merchant shipping act.

These rules need to be in line with the requirement of MLC and the ships registered under its flag need to have statement of compliance stating that the ships are in compliance with the requirements of MLC. This statement of compliance is required if the ships of these flags are visiting countries that have ratified the MLC convention.