Yes if you leave it in the fridge overnight the last bit in the bottom will dissolve but if you need to gentle rocking or rolling will get it done. I like to mix up 2 of the 24iu vials and backload 18 31g slin pins with 3iu. They are ready to pin just sitting in the butter bin.Interesting, yesterday when I reconstituted the HGH using Pfizer bac water, there was a small clump left over, but over time it dissolved when I gently rolled the vial between my hands. Is that a normal reaction? It’s labeled 24iu, but the test showed 27iu, so I rounded it to 26iu for easier calculations and added 2.6 ml of water.