• hypoglycaemia is defined as blood glucose of less than 4mmol/L
• it is a dangerous side effect of insulin therapy and sulphonylureas
• treat as an emergency regardless of level of consciousness

If blood glucose is not less than 4mmol/L but the patient is symptomatic, give a small carbohydrate snack for symptom relief.

For further information refer to NHS Lothian Intranet - Healthcare - Diabetes Metabolic Unit Handbook.                                                                                                                                      

Common causes of hypoglycaemia

• inadequate food intake, fasting, delayed or missed meals
• too much insulin or sulphonylurea
• insulin administration/drug administration at an inappropriate time
• problems with insulin injection technique/injection site causing variable insulin absorption
• increased physical activity
• alcohol

At risk groups

• strict glycaemic control
• impaired hypoglycaemic awareness
• cognitive impairment
• extremes of age
• breast feeding mother with diabetes

Conditions that increase risk of hypoglycaemia

• malabsorption
• gastroparesis
• abrupt discontinuation of corticosteroids
• hypoadrenalism
• renal or hepatic impairment
• pancreatectomy

Assess recent pattern of blood glucose levels - last 48 hours

• establish when and what the patient last ate
• check insulin/diabetes medication is being prescribed and administered at correct dose, time, and in relation to food intake
• check for signs of lipohypertrophy (lumpy areas at injection sites) which may affect insulin absorption
• check credibility of blood glucose monitoring, for example, handwashing before testing

• treat hypoglycaemia as per protocol
• consult diabetes team for advice if necessary
• establish the cause of hypoglycaemia and take action to prevent recurrence
• inform patient if medication dose is changed and provide information on hypoglycaemia management
• do not omit insulin in type 1 diabetes - treat hypoglycaemia and administer insulin as usual after dose review
• blood glucose is likely to be high following hypoglycaemia - additional correction doses should not be given
• if receiving IV insulin treatment, check blood glucose every 30 minutes until above 4.0mmol/L, then re-start IV insulin after review of infusion rates and requirement for IV insulin
• observe patient until recovery complete

Mild hypoglycaemia - patient conscious, orientated and able to swallow or,

Moderate hypoglycaemia - patient conscious and able to swallow, but confused, disorientated or aggressive

1. Give 15-20g of quick acting carbohydrate, such as glucose drink - Glucojuice 90-120ml or 150-200ml pure fruit juice or 4-5 Glucotabs.
2. If not capable and cooperative but can swallow, give 1.5-2 tubes of GlucoGel (squeezed into mouth between teeth and gums).
3. If ineffective, use 1mg glucagon IM.
4. Test blood glucose level after 10 - 15 minutes.
5. If still less than 4 mmol/L repeat up to 3 times.
6. If still hypoglycaemic, call doctor and consider IV glucose 10%  at 100 ml/hr or 1mg glucagon IM.                         

Once blood glucose level is above 4mmol/L

• Give 20g of long acting carbohydrate. For example:
  • 2 biscuits
  • slice of bread
  • 200-300ml milk
  • next meal containing carbohydrate
• Give 40g of long acting carbohydrate if IM glucagon has been used. For example:
  • 4 biscuits
  • 2 slices of bread
  • 400-600ml milk
  • next meal containing carbohydrate
• Do not repeat glucagon if it is ineffective - glucagon may take up to 15 minutes to work and may be ineffective in undernourished patients, in severe liver disease and in repeated hypoglycaemia
• Do not use in oral hypoglycaemic agent induced hypoglycaemia

For patients with enteral feeding tube 

• Give 50-70ml Glucojuice or Fortijuice
• Once glucose is greater than 4.0mmol/L restart feed /give bolus feed or start IV glucose 10% at 100ml/hr

If NBM, once glucose is greater than 4.0mmol/L give glucose 10% infusion at 100ml/hr until no longer NBM or reviewed by doctor

• Do not omit subsequent doses of insulin
• Review insulin/oral hypoglycaemic agent doses
• Contact the diabetes team if further education on hypoglycaemia is required

For further information refer to NHS Lothian Intranet-Healthcare-Diabetes-Metabolic Unit Handbook. 

Severe hypoglycaemia - patient unconscious/fitting or very aggressive or nil by mouth (NBM)

• Check ABC, stop IV insulin, contact doctor immediately
• Give IV glucose over 10-15 minutes as 75 ml glucose 20% or 150ml glucose 10% or 1mg glucagon IM
• Re-check glucose after 10 - 15 minutes and if still less than 4mmol/L, repeat treatment

Once blood glucose level is above 4mmol/L

• Give 20g of long acting carbohydrate. For example:
  • 2 biscuits
  • slice of bread
  • 200-300ml milk
  • next meal containing carbohydrate
• Give 40g of long acting carbohydrate if IM glucagon has been used. For example:
  • 4 biscuits
  • 2 slices of bread
  • 400-600ml milk
  • next meal containing carbohydrate
• Do not repeat glucagon if it is ineffective - glucagon may take up to 15 minutes to work and may be ineffective in undernourished patients, in severe liver disease and in repeated hypoglycaemia
• Do not use in oral hypoglycaemic agent induced hypoglycaemia

For patients with enteral feeding tube  

• Give 50-70ml Glucojuice or Fortijuice
• Once glucose is greater than 4.0mmol/L restart feed /give bolus feed or start IV glucose 10% at 100ml/hr

If NBM, once glucose is greater than 4.0mmol/L give glucose 10% infusion at 100ml/hr until no longer NBM or reviewed by doctor

• Do not omit subsequent doses of insulin
• Review insulin/oral hypoglycaemic agent doses
• Contact the diabetes team if further education on hypoglycaemia is required

For further information refer to NHS Lothian Intranet - Healthcare - Diabetes Metabolic Unit Handbook.