Southstar Drug is a chain of drugstores in the Philippines. It was established in 1937 as a small business venture engaged in the retail of Chinese herbal medicines, located in Naga City, Philippines. Southstar Drug was formerly known as Southern Drug (1937–1950) and New South Star Drug (1950–1990s). It faced competition from Mercury Drug (which has been the second oldest established drugstore chain eight years after Southstar Drug was established) and Watsons.
Today, Southstar Drug, otherwise known as SSD, belongs to the top 1,000 corporations of the Philippines. It has spread out its outlets with more than 500 branches nationwide. Currently, Southstar Drug has now owned by the Robinsons Retail Holdings, Inc., Philippines' second largest retail chain (which Robinsons had acquired Southstar in 2012).
Southstar Drug has expanded its business by putting up stores in Southern Luzon, Northern Luzon (following the acquisition of Manson Drug chain in 2011) and the islands of Mindoro, Masbate and Virac. South Star recently expanded in the Visayas region in 2010 (through its region's first branch in Samar). South Star sells fresh medicines and goods in remote communities.