This section is for everyone.
Basal insulin holds the blood sugar steady between meals and during sleep. A bolus is a dose of fast acting insulin given to cover meals or to reduce a high blood sugar.
Here are some popular ways of using these insulins.
Two mixed doses
Eg Novomix or Mixtard. The basal and bolus insulin is premixed in a fixed combination so that only two injections are needed in a day.
A high level of consistency is needed for meals and snacks. What is eaten and when it is eaten can be manipulated to give good results. The difficulty is that there is very little flexibility and you can’t just miss meals or eat more than usual and get away with it.
If your blood sugars are running high with this regime the main technique to get back in track is to give the injection and wait till the blood sugar has dropped before eating. Lows can also occur and you need to develop snacking routines to even these out.
This regime is often used for people who need help with their injections or who want to avoid injections such as younger school children and in the elderly or visually impaired.
Where money is an issue mixtard is cheaper than then newer analogue insulins.
The best coverage with this insulin is at breakfast and the evening meal. The injections are usually given 15-45 minutes before these meals depending on the type of fast acting insulin used. A lower carb meal can be eaten for lunch to help keep sugars normal. Alternatively a separate injection of regular or a rapid acting analogue can be given before lunch.
Morning mixed with evening split
Eg Mixtard am, Actrapid pm and Lente bedtime.
This regime covers the dawn phenomenon quite well because of the duration of the lente insulin. The mixed insulin in the morning means that injections during the school day can be avoided.
The minus points are a tendency for lows before lunch and high blood sugars after lunch.
This regime is not used frequently but it can suit some people very well. I know of a teenage girl who has a degree of intellectual impairment. She has a considerable dawn phenomenon. She uses this regime to avoid having to give insulin injections while she is at school.
Multiple daily injections with long acting basal
Eg Humalog for meals and snacks with Lantus once or twice a day.
This regime gives much more flexibility for meals than mixed insulin regimes.
The disadvantages are the number of injections. There can be 4-10 a day. Insulin pens are generally easier to carry but are more expensive than vials and syringes. The insuflon device can be useful for babies or toddlers on a MDI regime as the insulin is put in the same channel for a day or two so can be less uncomfortable.
This regime is the most popular for most older children and adults. In the USA all children are started on an intensive regime from diagnosis. In Europe there is more tendency to use a mixed regime at least to start with.
When it comes to advanced insulin techniques this is the method that I will mainly be discussing.
Insulin Pump Therapy
This is also known as a continuous subcutaneous insulin infusion system or CSII. It has been developed in the US and is much more popular there than in the UK.
Plus points are that finer tuning with insulin is possible with this technique particularly due to the ability to alter basal rates. Most people need to change the insertion device every 1-3 days. Once this is done there are a greater variety of bolus patterns you can use without having to have another injection. Many users love their pumps and greatly prefer it to the MDIs especially once over the first few months.
Disadvantages are that it is comparatively expensive. It costs about £5000 for a pump for five years use with an additional £1000 a year for sterile consumable supplies. You still need to have pens or vials and syringes handy in case of pump failure. It is available in some UK centres but the cost is not borne by the NHS and must be paid for in person or from a charity. A great deal of learning and monitoring is required to use this method successfully.
There are also problems that can occur on the short and long terms. Pump failure through the night can result in you going to bed with normal blood sugars and waking up in diabeticketoacidosis. Long term scarring at the infusion sites and the occasional abcess can also be problems that result in users going back to MDIs.
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Reference Info:
Acknowledgements to Dr Gary Scheiner’s Think Like a Pancreas.
Where to Next?
Please all continue to the How To: Calculate My Insulin Sensitivity section.