Hypoglycaemia in Adults with Diabetes Mellitus ( DM ) - The Hospital Management of

Publication: 22/11/2004  
Next review: 22/06/2025  
Clinical Guideline
ID: 3234 
Supported by: Inpatient Diabetes Safety Group
Approved By: Trust Clinical Guidelines Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2022  


This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

The Hospital Management of Hypoglycaemia in Adults with Diabetes Mellitus (DM)

Word version

Summary of Guideline/Protocol

Pertinent aspects of history and examination - Diabetes
Key diagnostic criteria - Capillary blood glucose (CBG) less than 4.0mmol
Investigations required - Capillary blood glucose
Treatment- See algorithm
Management- See algorithm

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To improve the diagnosis and management of Hypoglycaemia in Adults with Diabetes Mellitus (DM)

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Hypoglycaemic episodes are common, particularly with type 1 diabetes mellitus which is nearly always treated with insulin.

It may also occur in patients with type 2 diabetes, or other types of diabetes, depending on the treatment they are on.

Diabetes medicines fall into 2 groups as far as risk of hypoglycaemia is concerned.

Group 1: medicines which used alone, or in combination with any other diabetes treatment, can cause hypoglycaemia:
These are (i) all forms of insulin, (ii) sulphonylurea drugs (which include gliclazide, glimepiride, glibenclamide, glipizide) and (iii) non-sulphonylurea insulin secretagogues, which are nateglinide and rapaglinide.

Group 2: medicines which used alone, or in combination with other group 2 medicines, are very unlikely to cause hypoglycaemia.
These are (i) metformin (ii) pioglitazone (iii) gliptins (DPP-4 inhibitors) (iv) GLP-1 analogues (exenatide dulaglutide, liraglutide or semaglutide) and (v) acarbose (vi) SGLT-2 inhibitors (‘gliflozins’).

Hypoglycaemia in type 2 diabetes is more common in the elderly and those with acute kidney injury, or CKD.

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Link to enlarge flowchart  

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3. Establishing the Diagnosis of Hypoglycaemia

Hypoglycaemia is determined by a capillary blood glucose (CBG) measurement of <4.0mmol/L, performed by staff trained in the procedure.

The following symptoms may indicate a hypoglycaemic episode and should prompt confirmation by CBG measurement as above:

  • Autonomic symptoms – pallor, sweating, tremor, tachycardia
  • Neuroglycopaenic symptoms – loss of concentration, behavioural changes, fits, transient neurological deficits, reduced level of consciousness

Some patients especially with long standing Type 1 diabetes may lose their awareness of hypoglycaemia

Symptoms may be more unclear in the elderly

4. Risk Factors for Hypoglycaemia (Table 1)

Medical Issues

• Strict glycaemic control

• Previous history of severe hypoglycaemia

• Long duration of type 1 diabetes

• Duration of insulin therapy in type 2 diabetes

• Lipohypertrophy at injection sites

• Impaired awareness of hypoglycaemia

• Severe hepatic dysfunction

• Impaired renal function (including those people requiring renal replacement therapy)

• Sepsis

• Inadequate treatment of previous hypoglycaemia

• Terminal illness

• Cognitive dysfunction/dementia

• C-peptide negativity 

Reduced Carbohydrate Intake

•Food malabsorption e.g. gastroenteritis, coeliac disease, gastroparesis

• Bariatric surgery involving bowel resection 

Lifestyle issues

• Increased exercise (relative to usual)

• Increasing age

• Alcohol

• Early pregnancy

• Breast feeding

• No or inadequate blood glucose monitoring

Endocrine disorders

• Addison’s disease

• growth hormone deficiency

• hypothyroidism

• hypopituitarism

5. Potential Causes of Inpatient Hypoglycaemia (Table 2)

Medical Issues

• Acute discontinuation of long-term corticosteroid therapy

• Recovery from acute illness/stress

• Mobilisation after illness

• Major amputation of a limb

• Incorrect type of insulin or oral hypoglycaemia therapy prescribed and administered

• Inappropriately timed insulin or oral hypoglycaemia therapy in relation to meal or enteral feed

• Change of insulin injection site

• IV insulin infusion with or without glucose infusion

• Inadequate mixing of intermediate-acting or mixed insulins

• Regular insulin doses or oral hypoglycaemia therapy being given in hospital when these are not routinely being taken at home

• Failure to monitor blood glucose adequately whilst on IV insulin infusion

 Reduced Carbohydrate Intake

• Missed or delayed meals

• Less carbohydrate than normal

• Change of the timing of the biggest meal of the day (i.e. main meal at midday rather than evening)

• Lack of access to usual between meal or before bed snacks

• Prolonged starvation time e.g. ‘Nil by Mouth’

• Vomiting

• Reduced appetite

• Reduced carbohydrate intake

• Omitting glucose while on IV insulin infusion

 Insulin prescription errors

• Inappropriate use of ‘stat’ or ‘PRN’ rapid/ short-acting insulin (i.e. repeated doses of rapid- acting insulin without leaving sufficient time between to allow for onset of action and duration of effect)

• Confusing the insulin name with the dose (e.g. Humalog Mix25 becoming Humalog 25 units) and insulins with similar sounding names (e.g. Novorapid & Novomix 30)

• Confusing the concentration with the dose (be very careful if dose is written as 100units, it could be the insulin concentration instead which is usually 100units per ml • Only insulin syringes should be used to withdraw insulin from a vial, syringes used for intravenous administration should never be used for insulin.

• Inappropriately withdrawing insulin using a standard insulin syringe (100units/ml) from prefilled insulin pens containing higher insulin concentrations (e.g. 200units/ml or 300 units/ml)

• Misreading poorly written prescriptions – when ‘U’ is used for units (i.e. 4U becoming 40 units); always write “UNITS” in full

• Confusion regarding the indications for prescription of glucose and insulin infusion to control blood glucose and a glucose and insulin infusion for hyperkalaemia treatment (i.e. 50units in 50ml sodium chloride 0.9% instead of 10units of insulin with 25g glucose)

• Incorrect drug history and failure to correctly reconcile on admission

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  • If the capillary blood glucose concentration is <4.0mmol/l, send a venous blood sample to the laboratory for confirmation of the diagnosis if the patient is not responding to treatment, or the hypoglycaemic event is unexplained or suspicious
  • If the capillary glucose is <2 mmol/L, and this is either the first instance or it is an unexpected result, repeat the capillary measurement to confirm.
  • If the repeat capillary glucose is <2 mmol/L, take a fluoride sample for lab glucose (grey top) measurement and treat the patient (don’t delay treatment by waiting for the lab result)

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Treatment / Management

6. Treatment of Hypoglycaemia(if oral treatment appropriate, if not refer to Item 8 or Item 10)

A person experiencing hypoglycaemia requires quick acting carbohydrate (CHO) to return their blood glucose to the normal range eg, 4-5 glucose tablets (eg GlucoTabs) / 1 bottle of glucose liquid (e.g. GlucoJuice / Lift)

This quick acting CHO should be followed by a long acting CHO to maintain their blood glucose within the normal range (see 8.3 below).

Treatment should be commenced without delay.

7. Hypoboxes

A Hypobox containing all the first step options required to treat hypoglycaemia should be kept in a prominent place on the ward / department and it is the responsibility of the individual ward / Department to ensure that the box is re-stocked after use (See appendix 1 for list of contents).

Record in the clinical notes on patient electronic record (PPM):

  • The cause of the hypo & blood glucose readings
  • The treatment given
  • What action has been taken to prevent recurrence

Replace any contents used after each episode and as required.

Check box contents daily for expiry dates/suitability/availability for use

The flow chart shown at the beginning of the document summarises the treatment of hypoglycaemia                  

8. Special Considerations

8.1. Administering IV glucose 10%

  • Infusion should ideally be through a large vein.
  • Volume of infusion should be determined by clinical circumstances. (See below - 100ml bags of 20% glucose are available, and may be considered in the initial management of hypoglycaemia  in patients who are at risk of fluid overload eg, in renal failure or cardiac disease)

8.2. Glucagon

  • Should only be used once during treatment of a hypoglycaemic episode
  • Effect will wear off after approximately 30 minutes
  • Patients given glucagon will require a larger portion of long acting CHO to replenish glycogen stores
  • Glucagon will be less effective in patients with liver disease, glucocorticoid deficiency or who have been malnourished or starved & in those treated with sulphonylurea therapy

8.3. Suitable long acting carbohydrate (CHO) snack

  • 2 biscuits
  • 1 slice bread / toast
  • 200 – 300ml milk (not soya)
  • normal meal (must contain CHO)

8.4. Administering IV glucose 20%

  • 100ml bags of 20% glucose are available to give instead of 200ml 10% glucose over 15 minutes if the patient is at risk of fluid overload e
  • 500ml bags of intravenous glucose 20% solution are also available:
  • This can be used to treat severe or prolonged hypoglycaemia in special situations on the advice of a diabetologist, e.g. insulin or sulfonylurea overdose, or where smaller volumes of IV fluid are required.
  • Infusion should initially be through a large vein. Central intravenous access is necessary if use is likely to be prolonged (>4 hours).
  • Volume of infusion should be determined by clinical circumstances, eg, in renal failure or cardiac disease, smaller volumes may be required

9. Intravenous insulin and hypoglycaemia

If on variable rate IV insulin infusion ( VRII) and patient experiences hypoglycaemia:

  • reduce insulin infusion to 0.1 unit/hour, or consider stopping if the patient has long acting insulin on board
  • treat hypoglycaemia - See appendix 2 for further detailed guidance
  • when capillary blood glucose (CBG) >4.0mmol/l restore IV insulin infusion to an appropriate rate after reviewing the suitability of the prescription

If on fixed rate insulin infusion ( FRII) - see diabetic ketoacidosis ( DKA) guidance

9.1. Documentation

  • Document hypoglycaemic episode in the patient’s clinical notes and on the blood glucose monitoring chart 
  • Refer to the inpatient diabetes team if required, and document date and time of referral.

9.2. Monitoring, referral and admission / discharge

Consider risk factors and cause of hypoglycaemia

  • Review CBG record if available and consider whether diabetes treatment should be reduced
  • Do not omit next usual dose of insulin. Dose may require review though.
  • Do not treat isolated spikes of hyperglycaemia with “stat” doses of quick acting insulin.
  • Review CBG record and adjust usual diabetes treatment if a pattern is evident.
  • Patients should be advised to check their CBG concentration regularly for the next 48 hours, as an episode of hypoglycaemia increases the risk of further hypoglycaemia during this time. This may be done at home if patient safe for discharge.
  • Patients understanding of hypoglycaemia and corrective actions to take should be checked. If patient knowledge understanding deemed to be lacking, then refer to diabetes team for hypoglycaemia education.
  • Refer to diabetes team for hypoglycaemia education when hypoglycaemia is recurrent or unexplained.
  • Patients with Type 1 diabetes often do not require admission. Patients with Type 2 diabetes on sulphonylureas may need admitting as risk of hypoglycaemia can persist for 24 – 48 hours and a glucose infusion may be required. Patients requiring inpatient care should be triaged to diabetes and endocrinology team if patient has no other accompanying acute medical issues.

10. Adults requiring Enteral / Parenteral feeds

Patients requiring total parenteral nutrition (TPN) should be referred to a dietician / nutrition team, and diabetes team for individual assessment

10.1. Risk factors for hypoglycaemia:

  • Blocked/displaced tube
  • Change in feed regimen, enteral feed discontinued
  • Parenteral Nutrition or IV glucose discontinued
  • Diabetes medication given at inappropriate time to feed
  • Changes in medication that cause hyperglycaemia, eg, steroid therapy reduced / stopped
  • Feed intolerance
  • Vomiting
  • Deterioration in renal function
  • Severe hepatic dysfunction

10.2. Treatment to be administered via enteral feed tube (do not administer via the dedicated PN line)

Give 15 – 20g rapid acting carbohydrate via enteral feeding tube.

Use either:

  • 1 bottle of glucose liquid (e.g. GlucoJuice / Lift)


  • 50 – 70ml a juice-style supplement e.g. Fresubin Jucy / Fortijuce

Check blood glucose after 15 minutes.

If blood glucose remains below 4mmol/l repeat the above for a total of 3 cycles.

If blood glucose remains below 4.0mmol/l after 45 minutes (or 3 cycles) then consider IV glucose 10% infusion - 100ml/hour (volume as determined by clinical circumstances)

When blood glucose is above 4.0mmol/l and patient recovered give slower acting carbohydrate by either:

  • Restarting feed


  • If bolus feeding give additional bolus equating to  20g carbohydrate


  • 10% IV glucose infusion 100ml/ hr (volume should be determined by clinical circumstances).

Do not omit usual insulin injection if due, however a review of the dose may be required.

11. Patients on continuous subcutaneous insulin infusion (CSII) / ‘insulin pump’

Follow usual treatment for hypoglycaemia and then see below:

11.1 Patient able to manage their CSII

  • Unlike patient on long acting insulin, follow up with long acting carbohydrate is usually not required. If patient unclear on adjusting own insulin following hypoglycaemia, consider giving long-acting carbohydrate

11.2 Patient unable to manage their CSII ( unconscious / incapacitated patient)

  • Follow usual initial standard protocol for hypoglycaemic treatment as above

11.2.2 If hypoglycaemia is persistent despite multiple treatment attempts, consider removing cannula and insulin pump and advice patient to ‘restart’ their CSII. If patient is unable to do this, remove ‘cannula and pump’ and start alternative insulin regime. It is important that patient received alternative insulin regime ( s/c or IV insulin) within one hour of pump being removed to prevent development of diabetic ketoacidosis ( DKA). Further input from inpatient diabetes team needs to be obtained for further management and review.

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Record: 3234

To provide evidence-based recommendations for appropriate diagnosis, investigation and management of Hypoglycaemia in Adults with Diabetes Mellitus (DM).

Clinical condition:

Diabetes (Adults)

Target patient group: Adults with Diabetes (excluding critical care)
Target professional group(s): Pharmacists
Secondary Care Doctors
Secondary Care Nurses
Adapted from:

Evidence base


  1. The Hospital Management of Hypoglycaemia in Adults with Diabetes Mellitus, NHS Diabetes, September 2013 (and updated from updated guidance April 21) .

Evidence levels:

A. Meta-analyses, randomised controlled trials/systematic reviews of RCTs
B. Robust experimental or observational studies
C. Expert consensus.
D. Leeds consensus. (where no national guidance exists or there is wide disagreement with a level C recommendation or where national guidance documents contradict each other)

Approved By

Trust Clinical Guidelines Group

Document history

LHP version 1.0

Related information

APPENDIX 1 – Contents of Hypobox:


Quantity per box

Order numbers


Laminated copy of Hypoglycaemia algorithm



Laminated copy of box contents Daily check sheet



4 x 60ml bottles of 

glucose liquid (e.g. GlucoJuice / Lift) (15gms/60ml)



NHSSC - order number: AZB178 pack of 12

Glucose Tablets (eg Glucotabs)

(20 tablet blister pack)



NHSSC - order number:

AZB170 Pack of 6

Glucose 40% oral gel 2 x 3 25g triple pack

(eg Hypostop / Dextrogel / Glucogel)

2 Box (6 tubes)

Will be on your stock list from pharmacy 1 box contains 3 tubes

Glucagon -

Stored in the fridge 



Will be on your stock list from pharmacy


Quantity per box

Order numbers


Audit Booklet




Laminated copy of Hypoglycaemia algorithm



Laminated copy of box contents Daily check sheet



4 x 60ml bottles of 

glucose liquid (e.g. GlucoJuice) (15gms/60ml)



NHSSC - order number: AZB178 pack of 12

Glucose Tablets 4g

(20 tablet blister pack)



NHSSC - order number:

AZB170 Pack of 6

Glucose 40% oral gel 2 x 3 25g triple pack

(eg Hypostop / Dextrogel / Glucogel)

2 Box (6 tubes)

Will be on your stock list from pharmacy 1 box contains 3 tubes

Glucagon -

Stored in the fridge 



Will be on your stock list from pharmacy

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APPENDIX 2 - Use of IV glucose solutions in the management of hypoglycaemia

Glucose is given intravenously in two settings.

  • Firstly to provide a rapid supply of carbohydrate (sugar) for the initial treatment of hypoglycaemia in patients unable to take quick acting carbohydrate orally (patients who are unconscious or NBM). In this situation a stat dose of IV glucose is usually given over 10 – 15 mins and the guideline recommends the use of 200ml 10% glucose given over 15mins (infusion rate of 800ml/hr stopped after 15 mins) (or can consider using 100ml 20% glucose if the patient is at risk of fluid overload).
  • Intravenous glucose can also be prescribed to provide an ongoing supply of carbohydrate following the treatment of hypoglycaemia. In this situation 10% glucose given at a rate of 100ml/hr may be used.

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APPENDIX 3. Link to Poster of Human insulins on the formulary which includes information on their time action profiles:


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Appendix 4

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Equity and Diversity

The Leeds Teaching Hospitals NHS Trust is committed to ensuring that the way that we provide services and the way we recruit and treat staff reflects individual needs, promotes equality and does not discriminate unfairly against any particular individual or group.