VetriScience Laboratories - GlycoFlex 3 Hip and Joint Support for Dogs, 120 Bite Sized Chews The GlycoFlex Joint Support Stages System has been trusted and recommended by veterinarians for over 40 years. GlycoFlex has been Clinically Proven to increase hind leg strength in dogs by up to 41% in 4 weeks. GlycoFlex 3, our 3rd stage of joint support, is recommended for working dog breeds, very active dogs and senior dogs showing signs of joint health problems. Packaging May Vary.