Diabetes and Your Medication

What you should know about your diabetes and your diabetic medications

Metformin and B12 deficiency

Long term use of metformin, particularly for people on higher doses, can lead to lower levels of a nutrient called vitamin B12. This vitamin helps to keep red blood cells and nerves healthy.  

You should speak to your doctor if you develop new or worsening symptoms of extreme tiredness, a sore and red tongue, pins and needles, or pale or yellow skin, as these maybe signs of low vitamin B12 levels. A blood test maybe needed to investigate the cause of these symptoms. 

Do not stop metformin unless advised to do so by your doctor.  

 More information on Metformin can be found on the Diabetes UK website

Sodium Glucose Co-transporter-2 Inhibitors (SGLT2)

Medicines in the SGLT2 inhibitor class include canagliflozin, dapagliflozin, empagliflozin and ertugliflozin. These are otherwise more commonly known by the brand names Invokana, Forxiga, Jardiance and Steglatro. 

This video gives key information you should know about Forxiga, but this applies to all SGLT2 inhibitors.

SGLT2 inhibitors are prescribed in Type 2 Diabetes to reduce blood sugar levels but have further health benefits, such as reducing the risk of heart attacks and kidney disease. They work by making your kidneys remove some of the excess glucose (sugar) from your blood and then passing it into your urine to be removed from the body. 

However, small amounts of glucose may be left on the skin after urinating. Fungal organisms which are normally on your skin can grow more quickly than usual in your genital area because it is warm, damp, and sugary. This can commonly cause thrush or, on rare occasions,  more serious condition called Fournier’s Gangrene.

Please seek urgent medical treatment if you develop a temperature, an unpleasant smell and / or tenderness, redness and soreness in the genital area.

What is Diabetic Ketoacidosis?

Diabetic Ketoacidosis (DKA) is a condition that can affect both Type 1 and Type 2 diabetics.

DKA develops when there is not enough glucose entering the cells because there is not enough circulating insulin in the body. The body then begins to use its fat stores as an alternative source of energy. This results in toxic acidic ketones being produced, which disrupt the normal functioning of the body’s processes.

DKA develops due to an absolute lack of insulin in type 1 diabetes. It can affect Type 2 diabetic patients taking certain medications when they are unwell, are unable to eat and drink normally and are therefore at risk of dehydration.

The following are useful sources of information about DKA, including the signs and symptoms to look out for:

 Diabetes UK - Diabetic ketoacidosis (DKA) symptoms and treatment

 TrendDiabetes - Type 2 diabetes and diabetic ketoacidosis (DKA)

Understanding hypoglycaemia

Hypoglycaemia, or hypo, is the medical term for low blood glucose levels. This is when your blood glucose level drops below 4mmol/l. 

Even if you do not feel any symptoms, if you have a blood glucose reading of 4mmol/l or below you should treat it as a hypo. No matter how careful you are there could be times when you may experience hypos and knowing about them will help you feel prepared. 

Who is likely to experience a 'hypo'?

Anyone taking insulin or some types of oral hypoglycaemic medication, such as gliclazide.  Metformin is unlikely to cause hypoglycaemia. 

What symptoms should you look out for?

The symptoms associated with low blood glucose levels vary for individuals, but may include:

Early signs

  • Sweating and shaking
  • Trembling, hunger and headaches 
  • Blurred vision 
  • Tingling lips 

Later signs

  • Anxiety and irritability
  • Forgetfulness and confusion
  • Drowsiness
  • Speech difficulty
  • Lack of coordination
  • Unconsciousness

What causes a hypo?

A 'hypo' can be caused by the following:

  • Too much insulin  /too many tablets
  • Delayed or missed meal or snack
  • Not enough food – especially carbohydrate containing food such as bread, rice, pasta, potatoes etc.
  • Unplanned or strenuous activity
  • Drinking too much alcohol or alcohol without food

Be prepared - carry something to help treat a hypo at all times!

More information about hypos is available here:

 Bath RUH - Hypoglycaemia treatment for adults

 TrendDiabetes - Hypoglycaemia Explained

National shortage of glucagon like peptide-1 receptor agonists (GLP-1RAs)

There are very limited, intermittent supplies of all glucagon-like peptide-1 receptor agonists (GLP-1 RAs). These are better known as Ozempic (semaglutide), Saxenda (liraglutide) etc. Supplies are not expected to stabilise to meet full market demand until at least mid-2024.

More information on these types of medications can be found here

Diabetes UK has produced a helpful leaflet about the shortages, which can be read here. 

The supply issues have been caused by an increase in demand for these products for licensed and off-label indications. (The off-label use of these agents for the management of obesity is strongly discouraged.) The recommendation is that existing stock is conserved for use in patients with diabetes.

These shortages have serious clinical implications in the management of patients with type 2 diabetes. The clinical implications include erratic blood glucose control, with the potential to increase diabetes-related complications, including the risk of future cardiovascular events and diabatic ketoacidosis. 

The latest guidance on the shortages is as follows: 

Do not prescribe GLP-1 RAs outside of their approved use
Avoid starting people with Type 2 diabetes on any GLP-1 RAs
Do not switch between drug brands or substitute with lower dosages
Where alternative treatments need to be considered, discuss and agree a new management plan with those people affected, which might include starting insulin.

The Primary Care Diabetes Society (PCDS) and Association of British Clinical Diabetologists (ABCD) have also produced guidance which recommend supporting eligible people to access weight management and remission services.

Eligible people with Type 2 Diabetes Mellitus (T2DM) who would like support with weight management can be signposted the practice to available weight management programmes. In addition to local provision of weight management support, there are several nationally available options which patients might be interested in:

 NHS Digital Weight Management Programme

 NHS Better Health - Lose Weight

If this shortage is impacting on your mental health and wellbeing, you can call the Diabetes UK Helpline – call 0345 123 2399.