"Can they be used interchangeably?"
Foria Explore and Foria Relief are indeed very similar and can be used interchangeably for the most part. They both contain 60mg of THC and 10mg of CBD per individual suppository. The main difference is the carrier compound. Foria Relief is made with cocoa butter and Foria Explore is made with Jojoba essence. Jojoba essence is wax based and more latex friendly than cocoa butter. Personally, I love the smell of cocoa butter. Both products exist in a 2-pack and you can get Relief in a 4-pack and Explore in an 8-pack.