Tesamorelin is a powder medication that must be mixed with a liquid (diluent) before use. After mixing Tesamorelin with the diluent, it must be used immediately; do not store the mixture for later use. It is injected under the skin and usually given once a day. Use a different location on your tummy for each injection and do not inject into the same place twice in a row. Do not share the tesamorelin syringe either, even if the needle is changed.