INSULIN injectable

General information on use of insulin by SC route

Therapeutic action

• Pancreatic hormone, antidiabetic

Types of insulin

• For each preparation, onset and duration of activity are indicated by the manufacturer. Nevertheless, for the same preparation, onset and duration vary from one patient to another.
• In one same patient, duration of activity varies depending on the dose, site of injection, blood flow, body temperature and exercise.
• The type of insulin used depends of several factors: type of diabetes, patient's age, patient's response (blood glucose levels).
• Analogue insulins have a different chemical structure to human insulin that modifies their onset and duration of activity after SC injection.

Indications

• Type 1 and type 2 diabetes
• Diabetes during pregnancy
• Transient therapy of type 2 diabetes during periods of severe infection, trauma, surgery

Dosage

• Dosage must be individualised. Frequency of administration depends on the type of insulin and the patient's response. 

Duration

• Type 1 diabetes: life-time treatment
• Other indications: according to clinical response and laboratory tests

Contra-indications, adverse effects, precautions

• Do not administer in patients with allergy to insulin (rare).
• May cause :
  • hypoglycaemia due to overdosage or inadequate diet;
  • local reactions: pain, erythema at the injection site, lipodystrophy. Rotate injection sites systematically and use all available sites (abdomen, thigh, buttock or arm);
  • weight gain.
• Monitor combination with:
  • drugs enhancing hypoglycaemic effect of insulin: acetylsalicylic acid, angiotensin-converting enzyme inhibitors, beta-blockers (which in addition, may mask symptoms of hypoglycaemia);
  • drugs increasing blood glucose levels: corticosteroids, hydrochlorothiazide, salbutamol, chlorpromazine.
• Avoid alcohol (enhances and prolongs hypoglycaemic effect of insulin).
• In the event of renal or hepatic impairment and during the first trimester of pregnancy, reduce insulin doses. 
• In the event of infection, emotional stress, accident or surgical intervention and during the last 2 trimesters of pregnancy, increase insulin doses.
• Use sterile technique.
• Pregnancy and breast-feeding: no contra-indication

Remarks

• Insulin cannot be administered by mouth since it is inactivated in the gastrointestinal tract.
• After SC injection, insulin absorption is rapid in the abdomen, slower in thighs, buttocks and arms.
• When using an insulin pen, hold the needle in the skin at least six seconds to ensure the entire dose is injected.