Diabetes causes abnormalities in carbohydrate, fat, and protein metabolism due to insulin's ineffective action on target tissues. Insulin is a peptide hormone produced by the beta-cells of the pancreatic islets of Langerhans and is responsible for facilitating cellular glucose uptake and regulating carbohydrate, lipid, and protein metabolism. Insulin is injected into the fat layer subcutaneously, or beneath the skin. In this form of injection, a small needle is used to inject insulin into the fatty layer between the skin and the muscle. In comparison to a typical vial or syringe, the insulin pen was proved to be significantly easier to use and less unpleasant. Some characteristics of an insulin pen may make it more suitable for certain patients, and physicians must be aware of these requirements.

Keywords: Diabetes mellitus, Subcutaneous Insulin, Insulin pen, Insulin pump, Syringes, Insulin delivery.

1. Diabetes - WHO | World Health Organizationhttps://www.Available from: int › Health topics.
2. American Diabetes Association. Diagnosis and classification of diabetes mellitus. Diabetes Care. 2010;33 Suppl 1(Suppl 1): S62-S69. doi:10.2337/dc10-S062, PMID 20042775.
3. Watson S. Everything you need to know about diabetes, Healthline; Feb 26, 2020, Available from: https://www.healthline.com › health › diabetes
4. Matthew Hoffman MD. Diabetes Insipidus, WebMD,15; May 2020.
5. Slightham C. Everything you should know about diabetes insipidus (DI), Healthline,14; Feb 2020.
6. Obesity; preventing and managing the global epidemic. Report of a WHO consultation. World Health Organ Tech Rep Ser. 2000;894: i-xii, 1, 1-253.PMID 11234459.
7. Kahn CR. The molecular mechanism of insulin action. Annu Rev Med. 1985; 36:429-51. doi:10.1146/annurev.me.36.020185.002241, PMID 2986528.
8. Posner BI. Insulin signalling: the inside story.Can J Diabetes. 2017;41(1):108-113. doi: 10.1016/j.jcjd.2016.07, PMID: 27614806
9. Jardin-Fincati JR, Pavarotti M, Frendo-Cumbo S, Bilan PJ, Klip A. Update on GLUT4 vesicle traffic: A cornerstone of insulin action. Trends Endocrinol Metab. 2017 Aug; 28(8):597-611. doi: 10.1016/j.tem.2017.05.002, PMID: 28602209.
10. Wilcox G. Insulin and insulin resistance. Clin Biochem Rev. 2005 May;26(2):19-39. PMID 16278749.
11. Michael Dansinger MD. Types of insulin for diabetes treatment, Web Med, July 17 2020.
12. Wang W, Guo X, Shen G, Bai G, Wei Z, Liu J, Hirsch L, Strauss K. Skin and subcutaneous tissue thickness at insulin injection sites in Chinese diabetes patients: Clinical implications. Diabetes Metab. 2016 Nov;42(5):374-377. doi: 10.1016/j.diabet.2016.04.010, PMID: 27289143.
13. Koivisto VA, P. Felig Alterations in insulin absorption and blood glucose control associated with varying insulin injection sites in diabetic patients. Ann Intern Med. 1980;92 (1):59-61
14. John P. Cunha, et al Insulin regular HumanReviewed on 8/24/2021
15. Pérez A, Ramos A, Carreras G. Insulin therapy in hospitalized patients. Am J Ther. 2020 Jan/Feb;27(1):e71-e78. doi: 10.1097/MJT.0000000000001078, PMID: 31833876.
16. Botz CK, Leibel BS, Zingg W, Gander RE, Albisser AM. Comparison of peripheral and portal routes of insulin infusion by a computer-controlled insulin infusion system (artificial endocrine pancreas). 1976;25(8):691–700.doi: 10.2337/diab.25.8.691, PMID: 782981.
17. Van Dijk P. Intraperitoneal insulin.Diapedia Living Textbook of Diabetes. 
18. Prausnitz MR, Langer R. Transdermal drug delivery. Nat Biotechnol 2008;26(11):1261-8.doi: 10.1038/nbt.1504, PMID: 18997767
19. Cunha JP. FACOEP what is intravenous insulin therapy? Medicine Net.
20. Anders H, et al.Insulin delivery recommendations Vol 91(9); Sep 01, 2016. 1231-1255.
21. BD, Diabetes products, BD diabetes prod.[accessed Nov 21 2019].
22. Health line Insulin Injection Sites: Where and How to Inject Susan York Morris on; Aug 31, 2021.
23. American Diabetes Association. Insulin administration. Diabetes Care. 2004 Jan;27; Suppl1:S106-9. doi: 10.2337/diacare.27.2007.s106, PMID: 14693942.
24. Debra Manzella, RN. how to give an insulin injection, very well health 25; Aug 2021.
25. Shah RB, Patel M, Maahs DM, Shah VN. Insulin delivery methods: past, present and future. Int J Pharm Investig. 2016 Jan-Mar;6(1):1-9. doi: 10.4103/2230-973X.176456, PMID: 27014614.
26. JothydevKesavadev, et al. Evolution of insulin delivery devices: from syringes, pens, and pumps to DIY artificial pancreas diabetes Therapyvolume. 2020;11:1251–1269.
27. Singh R, Samuel C, Jacob JJ. A Comparison of insulin pen devices and disposable plastic syringes - simplicity, safety, convenience and cost differences. Eur Endocrinol. 2018 Apr;14(1):47-51. doi: 10.17925/EE.2018.14.1.47, PMID: 29922352.
28. Guerci B, Chanan N, Kaur S, Jasso-Mosqueda JG, Lew E. Lack of treatment persistence and treatment nonadherence as barriers to glycaemic control in patients with Type 2 diabetes. Diabetes Ther. 2019 Apr;10(2):437-449. doi: 10.1007/s13300-019-0590-x, PMID: 30850934.
29. Rees TM, Lennartz AH, Ignaut DA. A comparison of glide force characteristics between 2 prefilled insulin lispro pens. J Diabetes Sci Technol. 2015 Mar;9(2):316-9. doi: 10.1177/1932296814567533, PMID: 25591858.
30. Gudiksen N, Hofstätter T, Rønn BB, Sparre T. FlexTouch: an insulin pen-injector with a low activation force across different insulin formulations, needle technologies, and temperature conditions. Diabetes Technol Ther. 2017 Oct;19(10):603-607. doi: 10.1089/dia.2017.0121, PMID: 28704062.
31. Pohlmeier H, Berard L, Brulle-Wohlhueter C, Wu J, Dahmen R, Nowotny I, Klonoff D. Ease of use of the insulin glargine 300 u/ml pen injector in insulin-naïve people with type 2 diabetes. J Diabetes Sci Technol. 2017;11(2):263-269. doi: 10.1177/1932296816668877, PMID: 27664062.
32. Whooley S, Briskin T, Gibney MA, Blank LR, Berube J, Pflug BK. Evaluating the user performance and experience with a re-engineered 4 mm × 32g pen needle: a randomized trial with similar length/gauge needles. Diabetes Ther. 2019;10(2):697-712. doi: 10.1007/s13300-019-0585-7, PMID: 30809762.
33. Adam Felman What are insulin pens and how do we use them? Medical News Today on March 2019; 27.
34. Davis CP. Ph.D. medical definition of insulin pump Reviewed on 3/29/202.
35. Introduction to insulin patches published by Cleveland Clinic medical professional on 03/26/2021. Available from: https://my.clevelandclinic.org/health/articles/9811-insulin-pumps.
36. Accu-chek-combo-insulin pump published by Diabetes the global diabetes community on 15 January. 2019.
37. Lifescan Animas Vibe Insulin Pump Published by Diabetes the global diabetes community published on 15 January. 2019.
38. mini Med paradigm veoPublished by Diabetes the global diabetes community published on 15 January. 2019.
39. Insulin pump patchPublished by Diabetes the global diabetes community published on 15 January. 2019.
40. About insulin Published by Diabetes the global diabetes community published on 15 January. 2019.
41. Artificial pancreas Published by Diabetes the global diabetes community published on 15 January. 2019.
42. Michael Dansinger MD.What are insulin pump, wemed; Feb 7 202.
43. Insulin pump overview published by Endocrin web written by Grazia Aleppo. MD: FACE, FACP Updated on: 03/05/19. Available from: www.endocrineweb.com/guides/insulin/insulin-pump-overview.
44. Hoogma RP, Hammond PJ, Gomis R, Kerr D, Bruttomesso D, Bouter KP, Wiefels KJ, de la Calle H, Schweitzer DH, Pfohl M, Torlone E, Krinelke LG, Bolli GB; 5-Nations Study Group. Comparison of the effects of continuous subcutaneous insulin infusion (CSII) and NPH-based multiple daily insulin injections (MDI) on glycaemic control and quality of life: results of the 5-nations trial. Diabet Med. 2006 Feb;23(2):141-7. doi: 10.1111/j.1464-5491.2005.01738.x, PMID: 16433711.
45. BEST PRACTICE GUIDE CONTINUOUS SUBCUTANEOUS INSULIN INFUSION (CSII) A clinical guide for adult diabetes services published by ABCD DTN-UK. Available from:care/sites/abcd.care/files/BP_DTN_v13%20FINAL.pdf.
46. Fuld K, Conrad B, Buckingham B, Wilson DM. Insulin pumps in young children. Diabetes Technol Ther. 2010;12(S1);Suppl 1:S67-71. doi: 10.1089/dia.2009.0182, PMID: 20515310.
47. Steineck I, Cederholm J, Eliasson B, Rawshani A, Eeg-Olofsson K, Svensson AM, Zethelius B, Avdic T, Landin-Olsson M, Jendle J, Gudbjörnsdóttir S; Swedish National Diabetes Register. Insulin pump therapy, multiple daily injections, and cardiovascular mortality in 18,168 people with type 1 diabetes: observational study. BMJ. 2015 Jun 22;350:h3234. doi: 10.1136/bmj.h3234, PMID: 26100640.
48. Choudhary P, Rickels MR, Senior PA, Vantyghem MC, Maffi P, Kay TW, Keymeulen B, Inagaki N, Saudek F, Lehmann R, Hering BJ. Evidence-informed clinical practice recommendations for treatment of type 1 diabetes complicated by problematic hypoglycemia. Diabetes Care. 2015 Jun;38(6):1016-29. doi: 10.2337/dc15-0090, PMID: 25998294.

Aiswaria M

Pharm.D Intern, Swamy Vivekananda College of Pharmacy