Lyophilized formulations are a special type of injectable drugs developed from sterile injectable drugs using highly advanced technologies. A lyophilized drug is manufactured in a vacuum at extreme low temperatures using the principle of sublimation to remove water in the drug by changing its state directly from solid (ice) to gas (vapor). A lyophilized drug has a porous structure with sponge-like properties, which provide great rehydration ability while containing little water. Its size remains almost unchanged after freeze drying. It dissolves immediately in the water for injection. This process is able to keep the active ingredients of a drug contained and enhance their stability to achieve better efficacy.