Tresiba Penfil Injection 3 ml is used for the treatment of type 1 and type 2 diabetes mellitus in both children (above 1 year of age) and adults. It contain Insulin degludec, which is a fast-acting insulin that works rapidly to normalize blood sugar levels by helping the sugar move from the blood into other tissues of the body. It prevents the risk of having severe complications of diabetes. It stimulates the recovery of sugar in muscle and fat cells and thus suppresses the production of sugar in the liver. It may cause common side effects such as hypokalaemia (low potassium), hypoglycemia (low blood sugar level), local injection site reactions, lipodystrophy (fat deposition under the skin), rash, and pruritus (itch skin) which may occur at the injection site.