Prolotherapy injections can contain any number of natural substances that help stimulate a healing response. Traditional formulas may include dextrose, saline, Sarapin, P2G, and pumice. They are usually combined with local anesthetic agents like procaine and lidocaine to help reduce the pain of the injection. Recently, more advanced forms of Prolotherapy have emerged, including formulas with Platelet Rich Plasma (PRP) and adult stem cells.