Tips for injecting insulin

Jessica Oosthuizen shares some useful pointers when injecting insulin.

Insulin therapy remains a fundamental and essential part of diabetes management. Many patients with Type 2 diabetes and all patients with Type 1 diabetes require insulin to keep blood glucose within target ranges.

However, this practice is still not performed optimally in many healthcare facilities, and insulin therapy is only effective if delivered into the correct tissue in the correct way.

The goal of exogenous insulin (insulin that is not made by the body but injected) is to reliably deliver the medication into the subcutaneous tissue, without causing any pain or discomfort and without any leakage of insulin.

The aim is to prevent injecting into the muscle. Injecting into the wrong space can affect the absorption and action of insulin. This can lead to unpredictable blood glucose control. To achieve this objective, it is important to select a needle that is the correct length.

What needles should be used for injecting insulin?

Studies have shown that shorter needles of 4mm are as safe and well-tolerated in comparison to longer ones.

Needles come with a different diameter and length. Those with a higher gauge number have a smaller needle diameter. Needles are available in 4-, 5-, 6- or 8-mm. Needles with a length of 12,7mm have an increased risk of intramuscular injection (which you want to avoid).

It is often assumed that a heavier person, with a higher BMI, may require a longer needle. However, we now know that 4-, 5- or 6-mm needles are suitable for all people with diabetes. Regardless of their BMI.

Insulin therapy should ideally be started using shorter length needles and these injections should be given at 90 degrees to the surface of the skin.

Children and teenagers

Children and adolescents should only be using needles with a length of 4-, 5- or 6mm. There is no clinical reason for using needles longer than 6mm. When injecting insulin into limbs, a skin-fold may be necessary, especially when using a 5- or 6mm needle.


In adults, including those with a high BMI in the overweight or obese category,  a needle that is 4mm, 5mm or 6mm in length should be used. There is no clinical reason to be using a needle >8mm. Patients who are using these needles should ideally change to a shorter needle. If this is not possible then lifting a skin-fold and/or injecting at a 45 degree angle should be adopted to avoid an intramuscular injection.

Injecting insulin into the muscle will cause: your body to absorb it too quickly; a more painful injection; and a shorter duration of insulin action time.

How many times can you use the same needle?

In a perfect world insulin needles would be used once and then safely discarded. Yet, realistically it’s common practice for needles to be reused. Especially, in a country, like South Africa, where resources are limited in both state and private sectors.

Although the risk of complications is relatively low in relation to the reuse of needles, some evidence does show that the reuse of needles can cause an increased risk of lipohypertrophy. This refers to swelling of the fatty tissue under the skin which causes fat lumps. It’s a relatively common side effect of insulin injections and can occur if multiple injections are given around the same area repeatedly.

Lipohypertrophy causes inconsistent and unpredictable insulin absorption, which can result in unexplained hypoglycaemia and glucose variability. It is for this reason that proper rotation of injection sites and regular changing of needles is essential.

Priming your pen

It’s important to remember that your insulin pen device should always be primed before the first dose and after every needle change.

Priming helps to remove any air bubbles that can collect during everyday use of your pen and ensures that you receive the full dose when administering insulin.

To prime your pen, dial up 2 units, hold your pen with the needle facing upwards and press down on the plunger. If you see drops of insulin come out at the top of the needle, then you know that your pen has been primed.

However, if you don’t see a flow of insulin then you must repeat the steps and continue until drops of insulin are visible at the top of the pen.

These same steps can be followed if you notice an air bubble in your pen. If an air bubble is present and you don’t remove it then you will not receive the correct dose of insulin.

You will notice this when you inject yourself. The air bubble causes a negative pressure when pointing the needle downwards into your skin and you will see a flow of insulin that is not injected and rather ‘spills’ out when removing the needle.

Final comment

Choosing the correct needles and ensuring removal of air when priming your insulin pen are two things that are easy enough to do. They can have positive effects on blood glucose control for people living with diabetes requiring multiple daily injections.


  1. FIT forum for injection technique in South Africa. Recommendations for best practice in injection technique. 1st 2014.
  2. Kreugel, G., Keers, J., Kerstens, M. and Wolffenbuttel, B. (2011). Randomized Trial on the Influence of the Length of Two Insulin Pen Needles on Glycaemic Control and Patient Preference in Obese Patients with Diabetes. Diabetes Technology & Therapeutics, 13(7), pp.737-741.
  3. Shah, R., Shah, V., Patel, M. and Maahs, D. (2016). Insulin delivery methods: Past, present and future. International Journal of Pharmaceutical Investigation, 6(1), p.1.
  4. Frid, A., Kreugel, G., Grassi, G., Halimi, S., Hicks, D., Hirsch, L., Smith, M., Wellhoener, R., Bode, B., Hirsch, I., Kalra, S., Ji, L. and Strauss, K. (2016). New Insulin Delivery Recommendations. Mayo Clinic Proceedings, 91(9), pp.1231-1255.
  5. Bahendeka, S., Kaushik, R., Swai, A., Otieno, F., Bajaj, S., Kalra, S., Bavuma, C. and Karigire, C. (2019). EADSG Guidelines: Insulin Storage and Optimisation of Injection Technique in Diabetes Management. Diabetes Therapy, 10(2), pp.341-366.


Jessica Oosthuizen is a registered dietitian and works in private practice at the Wits Donald Gordan Medical Centre. Being a Type 1 diabetic herself, since the age of 13, Jessica has a special interest in the nutritional management of children and adults with diabetes. She also has a key interest in weight management and eating disorders.

LIKE THIS? ------------------------------------------------

SUBSCRIBE to our FREE Diabetes Focus Newsletter.

The Tshwane Insulin Project

Prof Paul Rheeder tells us more about the five-year research programme, the Tshwane Insulin Project (TIP).

About TIP

The University of Pretoria (UP) and Eli Lilly and Company will embark on a five-year research programme called, the Tshwane Insulin Project (TIP).

The aim of TIP is to optimise the control of blood glucose, blood pressure and lipids in people with diabetes, with specific reference to initiation and up-titration of insulin by both primary care nurses and/or primary care clinic physicians.

TIP is designed to fit into the National Department of Health’s Integrated Chronic Disease Management (ICDM). ICDM is a model of managed care that provides for integrated prevention, treatment and care of chronic patients at primary healthcare level, to ensure a seamless transition to assisted self-management within the community.

The TIP programme is a collaborative effort between the Departments of Internal Medicine, Family Medicine, Human Nutrition and the School of Health Systems and Public Health of UP, national and local health authorities, external experts and Eli Lilly.

The programme uses Lilly’s global health framework, which includes studying key research questions, reporting what works and what doesn’t, and then using the data to advocate for the scale up of the most effective solutions. The programme will contribute to Lilly 30×30. This is the company’s goal to create new access to quality healthcare for 30 million people in resource-limited communities every year by 2030.

Major challenge in SA

In SA, initiation and up-titration of insulin in primary care has been identified as a major challenge in diabetes care and achieving optimal insulin control. This is related to scarcity of resources, lack of healthcare practitioners trained in insulin use as well as patient-related factors, such as psychological insulin resistance

TIP is a much-needed project aimed at integrating diabetes care and especially initiation and up-titration of insulin by both primary care nurses and clinic physicians. Integrating prevention and effective treatment of diabetes and optimal glucose control is a crucial component of strengthening health systems and vulnerable communities where the impact of non-communicable diseases, like diabetes are often hardest felt.

UP has been involved in diabetes research in primary care for several years and through its research and training workshops, it has become clear that many patients in primary care are very poorly controlled.

One of the challenges with initiation and up-titration of insulin stems from the fact that insulin may legally only be prescribed by a doctor and not a nurse. Depending on the province and the district, many primary healthcare clinics do not have primary care physicians available full-time or even one day a week.

Many primary care physicians are also not confident in initiating and up-titrating insulin which leaves diabetes patients incredibly vulnerable and unable to access quality care close to their home.

Pathways to be taken

This programme is designed to explore the feasibility of using telemedicine or phone apps to assist the nurse or even the primary care physician to better serve the needs of people living with diabetes in underserved areas. It’s well-recognised that the major achievement of getting millions of people onto anti-retroviral treatment in SA was due to successful task-shifting using primary care nurses.

Inclusion of home visits by community healthcare workers will also be evaluated as they potentially could enhance compliance and patient education. TB care was also decentralised in a similar way and care and treatment was made available to patients as close to their homes as possible. We believe that the same can be achieved with diabetes care and we can avoid the current tragedy of people presenting at hospitals with advanced stages of diabetic co-morbidities and complications due to poor glucose control.

Comments from Eli Lilly

Evan Lee, Senior Director Global Health Programs and Strategy of Eli Lilly Global Health says diabetes is a major contributor to poverty and a barrier to social and economic development in developing countries like SA.

Diabetes is a growing problem worldwide, and its costs to society are high and escalating. It’s alarming when one considers that of the 10 leading causes of death in SA in 2016, five were non-communicable diseases and all had increased in 2016 compared with 2014. In fact, diabetes, which ranked third in 2014, moved to being the second most common natural cause of death in 2016, responsible for 5,5% of all deaths by natural causes. That’s 25 255 lives lost in 2016 alone, 69 deaths each day. Diabetes is ranked second only to tuberculosis and ahead of HIV, and in women, diabetes is the leading cause of death¹.

The importance of getting quality diabetes care embedded at a primary care level can’t be emphasised enough. Evidence shows that good diabetic control reduces the risk of diabetes complications and co-morbidities. This is a crucial aspect of the quality of life that a patient living with diabetes can expect to enjoy.

Therefore, finding new approaches to the detection and management diabetes, and bringing access to quality care to the community is so important. SA has been a pioneer in enabling care and management of complex diseases, like HIV and MDR-TB. So, it should be feasible to do so for diabetes.

By working closely with the UP and local municipal clinics, we aim to transfer the learnings from this research project to other regions in SA. By rigorously documenting, monitoring and evaluating the intervention, we hope this project will be shared nationally and the massive impact of diabetes, especially on vulnerable communities, can be halted.

References:, Appendix M


Professor Paul Rheeder is a trained specialist physician with a PhD in clinical epidemiology obtained from Utrecht University, the Netherlands. He occupied the Medihelp Chair in clinical epidemiology at UP for 10 years. He is past acting head of the School of Health Systems and Public Health, UP. Currently he is employed as senior specialist physician at the Steve Biko Academic Hospital, Department of Internal Medicine. His main research interest is in improving management and outcomes of patients with diabetes mellitus.

Making insulin work for the diabetic, and not the other way around

Michelle Carrihill educates us on how to use various insulins with their unique actions to meet the desired requirements.

There is no ‘easy-peasy’

As a student, I remember being taught that the only thing wrong with a Type 1 diabetic is that they are deficient in insulin. So, the treatment is simple – replace the insulin, and all is returned to normal. Easy-peasy.

Except it is not. Each person is an individual. Each person has variable insulin requirements, and these may change minute-to-minute, hour-to-hour, day-to-day, week-to-week, and especially year-to-year as the body grows and changes.

Very few people have predictable, regular lives. Nevermind predictable regular metabolic rates. Add the variability that is introduced with different amounts and types of carbohydrates, plus protein and the altered absorption with fat in a meal; throw in exercise, emotions and stress, and it might feel almost impossible to exactly figure out which insulin and how much of it should be given at any one time.

Another factor is that each individual may respond slightly differently to a brand or type of insulin, and that the individual’s response may not be the same at each injection.

Also, unlike the insulin produced naturally, once insulin is injected in the body, it cannot be switched off. Once it is in the body, it will continue working, whether needed or not!

Individualise insulin treatment

The most important thing is to individualise the insulin treatment regimen to best fit the individual’s needs. Obviously, the available insulins, the budget and the willingness of the diabetic (or their carer) to test sugar levels and adjust doses are important to take into consideration when designing insulin replacement therapy.

To understand this, let’s look at the available insulins, and their action times. This information is provided by each of the manufacturers.


Type of Insulin & Brand Names




Role in Blood Sugar Management


Lispro (Humalog) 15-30 min. 30-90 min 3-5 hours Rapid-acting insulin covers insulin needs for meals eaten at the same time as the injection.
Aspart (Novorapid) 10-20 min. 40-50 min. 3-5 hours
Glulisine (Apidra) 20-30 min. 30-90 min. 1-2 1/2 hours


Regular (R)


Biosulin R

Humulin R

Insumam R

30 min. -1 hour 2-5 hours 5-8 hours Short-acting insulin covers insulin needs for meals eaten within 30-60 minutes



Biosulin N

Humulin N

Insumam N




1-2 hours



4-12 hours

18-24 hours Intermediate-acting insulin covers insulin needs for about half the day or overnight.


Insulin glargine (Basaglar, LantusToujeo, Optisulin) 1-1 1/2 hours No peak time. Insulin is delivered at a steady level. 20-24 hours Long-acting insulin covers insulin needs for up to one full day.
Insulin detemir (Levemir) 1-2 hours 6-8 hours Up to 24 hours
Insulin degludec (Tresiba) 30-90 min. No peak time 42 hours


Humulin 30/70


30 min. 2-4 hours 14-24 hours These products are generally taken twice a day before main meals.
NovoMix 30 10-20 min. 1-4 hours Up to 24 hours
Humalog mix 25 15 min. 30 min.-2 1/2 hours 16-20 hours
*Premixed insulins combine specific amounts of intermediate-acting and short-acting insulin in one bottle or insulin pen. (The numbers following the brand name indicate the percentage of each type of insulin.)

If you combine these insulin profiles, and superimpose them over what the individual’s insulin requirements are, you then get to understand when the insulin will be working for them, and which combination will suit their needs. These needs may vary from time-to-time and over time, so it is important they monitor their sugars, either with finger-prick tests, or if viable, a continuous glucose monitor.

Let’s look at some regimens:

Twice a day insulin

Benefits: Disadvantages:
Easiest regimen Must be given 30 minutes before the meals.
Only two injections a day Midmorning snack required.
Lunch carbohydrates may not be adequately covered.
No flexibility in meal component of the insulin (if using a premixed insulin combination).
The intermediate-acting insulin given before an early dinner may mean inadequate basal cover by the early morning – a risk of waking up with a high fasting sugar, and some ketosis.

 Three times a day insulin

Benefits: Disadvantages:
Covers overnight requirements better by the later injection of the intermediate insulin, decreasing the chance of morning high levels. Regular insulin must be given 30 minutes before the meals.
Midmorning snack required.
Lunch carbohydrates may not be adequately covered.
Requires a bedtime snack.

 Basal bolus regimen

Benefits: Disadvantages:
Flexible dosing for carbohydrates and correcting. In-between meal carbohydrates need to be counted and dosed for. Or carbohydrate free snacks considered.
More frequent injections (and testing) required.
More expensive.

 Long-acting insulin analogues

Benefits: Disadvantages:
Flexible dosage for carbohydrates and correcting. ‘In-between’ meal carbohydrates need to be counted and dosed for. Or carbohydrate free snacks considered.
Fasting is possible. More frequent injections (and testing) required.
Flexibility in the timing of the meals/snacks. Much more expensive.
Less risk of nocturnal hypoglycaemia.
No need for night time snack.

Continuous sc insulin infusion

Benefits: Disadvantages:
Built in calculator for carbohydrate counting and corrections. Only rapid insulin is used, so any disruption in delivery can rapidly lead to ketoacidosis.
Insulin can be suspended. Very expensive.
Basal rates can be individually set. Needs high quality training and ongoing interaction.
Dawn phenomenon can be covered. Permanently attached to a device.
Fasting easy to achieve.
Temporary increase or decrease in basal requirements easy to achieve.

Mix and match

Mixing and matching of insulins is also possible. For example, a child attending primary school might do well on regular and intermediate-acting insulins half an hour before breakfast, without requiring any insulin for their school break; a rapid insulin analogue for after-school lunch and dinner; and then a long-acting basal analogue for their basal insulin overnight.

As mentioned already, monitoring the blood glucose then opens the eyes to the effect of the insulin doses – both for the individual dose, as well as for the pattern of dosing. Fasting sugars reflect the long-acting doses and post-meal levels reflect the bolused doses for carbohydrates and corrections.

Carbohydrate counting affords the closest-to-physiology use of mealtime insulin, and is to be encouraged. Even if using a fixed-dose insulin regimen, knowing how much carbohydrate is in a meal allows for consistency of insulin to carbohydrate dosing – which then helps prevent sugar variability after meals.

Monitoring sugar levels before and after activities and sports helps with planning of extra carbohydrates or a change in insulin dose for the meal before or after the exercise.

The message is that getting sugars to target is possible by knowing what the individual needs, and using the available insulins to suit those needs. Monitoring sugars and adjusting doses and types of insulin along the way will keep the person with diabetes healthy, and able to get on with living their lives.


Dr Michelle Carrihill is a paediatric endocrinologist working with children and adolescents with diabetes and chronic endocrine and metabolic conditions. She runs the adolescent sub-speciality ward at Groote Schuur Hospital and has a large ambulatory service for the chronic medical needs of these patients.

Remembering the old days of insulin

The discovery of insulin is one of the most enthralling detective stories filled with drama, intrigue and competition. Noy Pullen introduces us to two of the first insulin patients and how the discovery changed their lives.

First people treated with insulin

Imagine the medical world before insulin was discovered in 1921. This was what Leonard Thompson and Elizabeth Hughes had to face when they were diagnosed with diabetes mellitus some years prior to this.

Leonard Thompson. Photo courtesy of Eli Lilly and Company Archives. Copyright Eli Lilly and Company. All Rights Reserved.

Leonard Thompson

Leonard Thompson was the first patient treated with insulin by Dr Fred Banting, one of the four researchers credited with the discovery of insulin.

When Leonard was taken, by his father, to the Toronto General Hospital, Leonard weighed 65 pounds (22,6kg), and was drifting in and out of a diabetic coma.

As a result, Leonard’s father agreed to let the doctors inject Leonard with this new fluid, called insulin, made from bovine pancreas. Within days, a miracle had taken place as the 14-year-old regained his strength. He went on to enjoy another 13 years of life, dying from pneumonia. When told of the news, Banting’s comment was, “I hope he had a good life,”

Elizabeth Hughes

Elizabeth Hughes, daughter of a prominent politician, was one of the first Americans to receive insulin. She had been a sporty child with great dreams when, aged 11, she was diagnosed with diabetes.

Diagnosed in 1919, she struggled through three years of the only treatment used then: starvation therapy. She hoped she would live until insulin was past the experimental stage.

She found solace in reading, which did not tax her strength and ignited her dreams to travel to all the wonderful places she had read about.

Not her mother’s pleading nor her father’s position and influence could help at this stage. She took in less than 300 calories a day and exercised conscientiously.

Elizabeth Hughes

Starvation therapy

Before 1921, Dr Frederick Allen, ‘father’ of the starvation therapy method, ran a successful clinic in America for those living with diabetes Type 1.

A starvation diet was worked out for patients; keeping them alive yet free from blood sugar in the urine. It has been reported that Dr Allen ran his clinic like a military operation and patients were locked away for up to five months.

One British patient, Rene Mason, recalled, “Before I was put on to insulin I was starved. My mother would lock the larder. I would steal the dog biscuits.” Another patient on starvation therapy, John Johnson, recalled being forced to live on boiled cabbage water from Friday to Monday.

While on the diet, one of Dr Allen’s young patients kept having high sugar levels. After interrogation, the patient admitted that he secretly ate toothpaste and the bird seed meant for his canary, which he had cunningly asked for as a pet.

Another enterprising patient, on the third floor, made a deal with the newspaper boy to tie sweets onto the end of a long piece of string every day.


Margaret Kienast, a nurse who worked with Dr Allen recalled, “The hope of insulin cajoled the patients into new life. Diabetics, who had not been out of bed for weeks, began to trail about, clinging to walls and furniture.”

When Dr Allen appeared in the doorway, after visiting Dr Fred Banting on the patients’ behalf, he caught the beseeching gaze of hundreds of pairs of eye. “I think I may have something for you,” he said softly.

Consequently, Elizabeth Hughes – who was in Dr Allen’s clinic – became Banting’s prize patient. In hand-written notes, he described what he saw: weight 45lbs (20kg); height 5ft (1,5m); extremely emaciated; slight oedema of the ankles; skin scaly and dry; hair brittle and thin; muscles extremely wasted; subcutaneous tissue almost completely absorbed; and scarcely able to walk due to weakness.

The change in Elizabeth was described as dramatic – almost magical. Furthermore, it has been reported that she said, “Oh, it’s simply too unspeakably wonderful for words, this stuff…To think I’ll be leading a normal healthy existence is beyond all comprehension!”

Samples of insulin from the early days of the drug’s development. Photo by SSPL/Getty Images.

A good life on insulin

As a result, Elizabeth went on to graduate from college, got married, and had three children. None of whom ever knew of her secret regime. They would see their mother disappear into her room each day at 5:30, in the evenings, but never knew what she was doing there.

She was always strict with her diet and exercise while travelling widely. She lived a healthy life to the age of 74, with no complications.

So, Elizabeth Hughes demonstrated that it was her attitude to life, her ‘inner conductor’ of her choices, that guided the rhythm of her life. No one else directed her.

Probably, many people with diabetes feel the oppressiveness of the cage of chronic illness, the diet and insulin dependence. Yet, Elizabeth found insulin liberating. Most of all, she found it to be a miracle substance which transformed her life.

Therefore, much can be learnt from reflecting on the history of people living with diabetes, and how current individual reflection influences the possibility for leading a healthy life with diabetes.

Accounts of this marvellous discovery can be found in two highly recommended books by the renowned Canadian historian, Michael Bliss – ‘The Discovery of Insulin’ and ‘Banting – A Biography’. Anyone who reads these will never see insulin in the same light again.


Please contact Noy Pullen if you would like more information on her resources: [email protected] or 072 258 7132.



The story of insulin through the ages

The story of insulin discovery and development to where we are today reflect the ingenuity of scientists and their persistence in exploring, investigating and improving medicines to ultimately treat patients better. I was reminded of this when a patient of mine, who has been living with diabetes for 35 years, told me how she would use a Bunsen burner to sterilise her needles, and dilute her urine with water so it would not show up dark if her sugar was high – all to placate her mother! How far have we come?