[7] Common side effects include low blood sugar, problems at the site of injection, itchiness, and weight gain.

[16] However, a 2004 study found that mixing glargine with other insulins did not affect short-term glycemic profile.

[17] Common side effects include low blood sugar, problems at the site of injection, itchiness, and weight gain.

In the neutral subcutaneous space, higher-order aggregates form, resulting in a slow, peakless dissolution and absorption of insulin from the site of injection.

[22] A three-fold more concentrated formulation, brand name Toujeo, was introduced after FDA approval in 2015.

[27] In March 2018, insulin glargine (Semglee) was approved for medical use in the European Union.

[28] In July 2021, insulin glargine-yfgn (Semglee) was approved for medical use in the United States as the first interchangeable biosimilar of Lantus.

[29] Insulin glargine from competitor Eli Lilly became available in most countries during 2015, under the brand names Basaglar (as a follow-on in the US) and Abasaglar (as a biosimilar in the EU).