Asparaginase is an enzyme that is used as a medication and in food manufacturing. As a medication, L-asparaginase is used to treat acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL). It is given by injection into a vein, muscle, or under the skin. A pegylated version is also available. In food manufacturing it is used to decrease acrylamide. Common side effects when used by injection include allergic reactions, pancreatitis, blood clotting problems, high blood sugar, kidney problems, and liver dysfunction. Use in pregnancy may harm the baby. As a food it is generally recognized as safe. Asparaginase works by breaking down the amino acid known as asparagine without which the cancer cells cannot make protein. The most common nonhematological adverse reactions of asparaginase erwinia chrysanthemi (recombinant) include abnormal liver test, nausea, musculoskeletal pain, infection, fatigue, headache, febrile neutropenia, pyrexia, hemorrhage (bleeding), stomatitis, abdominal pain, decreased appetite, drug hypersensitivity, hyperglycemia, diarrhea, pancreatitis, and hypokalemia. Asparaginase was approved for medical use in the United States in 1978. It is on the World Health Organization's List of Essential Medicines. It is often made from Escherichia coli (E. coli) or Erwinia chrysanthemi. Uses Asparaginases can be used for different industrial and pharmaceutical purposes. Medical E. coli strains are the main source of medical asparaginase. Branded formulations (with different chemical and pharmacological properties) available in 1998 include Asparaginase Medac, Ciderolase, and Oncaspar. (Crasnitin has been discontinued.) Spectrila is a recombinant E. coli asparaginase. Asparaginase produced by Dickeya dadantii (formerly called Erwinia chrysanthemi) instead is known as crisantaspase (BAN), and is available in the United Kingdom under the brand name Erwinase. One of the E. coli asparaginases marketed under the brand name Elspar for the treatment of acute lymphoblastic leukemia (ALL) is also used in some mast cell tumor protocols. On July 24, 2006, the U.S. Food and Drug Administration (FDA) granted approval to pegaspargase for the first-line treatment of patients with ALL as a component of a multiagent chemotherapy regimen. Pegaspargase was previously approved in February 1994 for the treatment of patients with ALL who were hypersensitive to native forms of L-asparaginase. On December 20, 2018, the FDA approved calaspargase pegol-mknl, an asparagine specific enzyme, as a component of a multi-agent chemotherapeutic regimen for ALL in pediatric and young adult patients age 1 month to 21 years. This new product provides for a longer interval between doses compared to other available pegaspargase products. Calaspargase pegol-mknl