Humulin R (Insulin Human)

Humulin R is employed to lower elevated blood glucose levels in diabetic patients.

• Type 1 diabetes mellitus, where endogenous insulin production is absent.
• Type 2 diabetes mellitus, as part of a regimen that includes diet, exercise, and other glucose‑lowering agents.
• Rapid correction of post‑prandial glucose excursions.
• Management of hyperglycemia in hospitalized or surgical patients requiring short‑acting insulin.
• Adjunct therapy during pregnancy when a short‑acting insulin is preferred.

• Humulin R consists of recombinant human insulin that binds to insulin receptors on muscle, adipose and hepatic cells. Receptor activation triggers autophosphorylation and downstream signaling through the PI3‑K/Akt pathway, facilitating translocation of GLUT‑4 transporters to the cell surface and enhancing glucose uptake. In the liver, the drug suppresses gluconeogenesis and glycogenolysis, thereby reducing endogenous glucose production and lowering circulating blood glucose concentrations.

Adverse reactions to Humulin R vary in frequency and severity.

Common

• Hypoglycemia, especially if meals are delayed or doses are excessive.
• Injection site reactions such as redness, swelling, or itching.
• Lipodystrophy, including lipohypertrophy at repeated injection sites.
• Weight gain associated with improved glycemic control.

Serious

• Severe hypoglycemia leading to loss of consciousness or seizures.
• Allergic reactions ranging from urticaria to anaphylaxis.
• Edema or fluid retention.
• Rare cases of insulin antibody formation causing insulin resistance.

When prescribing or using Humulin R, clinicians and patients should consider several safety considerations.

• Adjust dose in renal or hepatic impairment to avoid hypoglycemia.
• Monitor blood glucose closely during illness, stress, or changes in diet.
• Use lower initial doses in insulin‑naïve patients, particularly children and the elderly.
• Educate patients on proper injection technique and site rotation to reduce lipodystrophy.
• Review concomitant medications that may mask hypoglycemia symptoms.
• Avoid use during episodes of severe hypoglycemia until cause is identified.
• Pregnancy and lactation decisions should be made by a healthcare professional.

Humulin R may interact with other medicines, influencing its glucose‑lowering effect or increasing the risk of adverse events.

Avoid

• Concurrent use of other rapid‑acting insulins or insulin analogues without dose adjustment.
• Beta‑blockers that can mask hypoglycemia symptoms.

Use with caution

• Oral hypoglycemic agents (e.g., sulfonylureas, meglitinides) that increase hypoglycemia risk.
• Corticosteroids, which may raise blood glucose and require higher insulin doses.
• Diuretics, particularly thiazides, that can affect electrolyte balance and glucose control.
• Alcohol, which can cause delayed hypoglycemia after insulin administration.