Regular insulin

Regular insulin, also known as neutral insulin and soluble insulin, is a type of short-acting medical insulin.^[2] It is used to treat type 1 diabetes, type 2 diabetes, gestational diabetes, and complications of diabetes such as diabetic ketoacidosis and hyperosmolar hyperglycemic states.^[5] It is also used along with glucose to treat high blood potassium levels.^[6] Typically it is given by injection under the skin, but may also be used by injection into a vein or muscle.^[2] Onset of effect is typically in 30 minutes and it typically lasts for 8 hours.^[5]

Regular insulin

A vial of regular human insulin
Clinical data
Trade names	Humulin R, Novolin R, Actrapid, others[1][2]
Other names	insulin injection (soluble),[2] neutral insulin,[2] regular human insulin, human insulin (regular), Toronto insulin
Biosimilars	Myxredlin[3]
AHFS/Drugs.com	Monograph
MedlinePlus	a682611
License data	US DailyMed: Humulin
Routes of administration	Subcutaneous, intramuscular, intravenous[2]
ATC code	A10AB (WHO)
Legal status
Legal status	CA: ℞-only / Schedule D[3] US: OTC / Rx-only[4]
Pharmacokinetic data
Onset of action	30 minutes
Duration of action	8 hours
Identifiers
CAS Number	9004-10-8 Y 11061-68-0 (insulin human)
ChemSpider	none
UNII	1Y17CTI5SR

The common side effect is low blood sugar.^[5] Other side effects may include pain or skin changes at the sites of injection, low blood potassium, and allergic reactions.^[5] Use during pregnancy is relatively safe for the baby.^[5] Regular insulin can be made from the pancreas of pigs or cows.^[2] Human versions can be made either by modifying pig versions or recombinant technology.^[2]

Insulin was first used as a medication in Canada by Charles Best and Frederick Banting in 1922.^[7] It is on the World Health Organization's List of Essential Medicines.^[8] In 2017, it was the 209th most commonly prescribed medication in the United States, with more than 2 million prescriptions.^[9] Versions are also available mixed with longer-acting versions of insulin, such as NPH insulin.^[2] In 2020, the combination of human insulin with insulin isophane was the 246th most commonly prescribed medication in the United States, with more than 2 million prescriptions.^[10][11]

Medical uses

Regular insulin is used for the long-term management of diabetes.^[5] It is the treatment of choice for the two diabetic emergencies diabetic ketoacidosis and hyperosmolar hyperglycemic states.^[5] It may also be used in combination with glucose to lower potassium levels in those with hyperkalemia.^[6]

Side effects

Side effects may include: low blood sugar levels, skin reactions at the site of injection and low potassium levels among others.^[5]

Manufacture

Humulin, one brand name for a group of biosynthetic human insulin products, is synthesized in a laboratory strain of Escherichia coli bacteria which has been genetically altered with recombinant DNA to produce biosynthetic human insulin. Humulin R consists of zinc-insulin crystals dissolved in a clear fluid.^{[citation needed]}

Formulations

It is sold by many manufacturers in a number of different forms.

By Eli Lilly these include:^{[citation needed]}

• Humulin R (REGULAR human insulin injection [rDNA origin]) is a short-acting insulin that has a relatively short duration of activity as compared with other insulins.
• Humulin R Regular U-500 (Concentrated) insulin human injection, USP (rDNA Origin) is a stronger concentration (500 units/mL) of Humulin R.
• Humulin 70/30 (70% human insulin isophane suspension, 30% human insulin injection [rDNA origin]) is a mixture insulin. It is an intermediate-acting insulin combined with the onset of action of Humulin
• Humulin 50/50 (50% human insulin isophane suspension, 50% human insulin injection [rDNA origin]) is a mixture insulin. It is an intermediate-acting insulin combined with the onset of action of Humulin R.

In UK these include:^[12]

• Actrapid
• Humulin S
• Insuman Rapid