Insulin — A Learning Curve


One of the things I keep saying is that controlling diabetes is a juggling game.  You need to juggle your physical activity with your diet and last but far from Least is your daily injections. Type-1 or juvenile diabetes as it is sometimes known almost always requires injections.  If you’re a type-2 diabetic there is also a chance you might be on injections if you haven’t managed to control the disease with pills, diet and exercise. Even with insulin injections if you think it’s easy to achieve perfect  blood sugar levels and control then apparently you’re NOT a diabetic.   Maybe if we  lived in an imaginary world where we ate, slept  and exercised  exactly the  same thing every day then maybe it would be ALMOST possible  — but unfortunately most diabetics don’t  live in the land of OZ or some other imaginary place. This brings me to the point of this post — knowing the ins and outs of the INSULINS you take or at least the basics…

We take insulin injections because for whatever reasons  our bodies  (pancreas to be exact)  just doesn’t produce enough or efficient enough insulin (which is a hormone)  to regulate the  glucose (sugar) levels  in our blood.   In order to regulate blood sugar  diabetics need to take daily injections.  It’s supposed to do what the pancreas does or at least produce something that the pancreas produces and doesn’t work well or at all in diabetics.  Simple — well yes and no…  Taking an injection is quite simple but getting it to work for you to control your blood sugar levels is not that simple as any diabetic can tell you.  The human body is an unbelievable machine when it works well —  when things don’t work well it’s very hard to achieve a replacement in the laboratory.  That said — most type-1 diabetics would not be alive today without this wonderful thing called INSULIN.

The thing with insulin injections  that separates it from the insulin produced by your body  is  that your body is an unbelievable computer that knows just when to produce the insulin and also the right amount of insulin  to control any  blood sugar spurts and hopefully keep your blood sugar levels  in the normal range (~80 to ~120).  An insulin injection however follows a pretty strict CURVE.  The insulin injection starts working after a certain amount of time, reaches a peak performance after a certain amount of time and then tapers down and  magically stops working entirely.  In short – in  order to control your diabetes you need to know your insulin injection curves.

I won’t go into all the different insulin types and their curves for the simple reason that I don’t know all the different insulin types out there (I’m not a diabetes physician or specialist ) — but I will however discuss the ones I do know a thing or two about (mainly because I’ve used them… which hopefully will help me make my points clear!!).

For many years I used to take  a combination of regular and NPH insulin because that’s what was available at the time  and that’s what my diabetic specialist prescribed.  Here’s the curves of the way  these 2 insulins work:

Regular Insulin:  Onset = 1/2 hour to 45 minutes. Peak = 2 to 3.5 hours. Total Duration = 5-7 hours.

NPH Insulin: Onset =  1 to 3 hours. Peak – 4 to  9 hours.  Total Duration = 14-20 hours.

Now let’s look at the CURVES of these insulins and the  challenges they presented me .   Let’s say I’d get up in the morning with a normal blood sugar level ….  I now start off the day by taking my NPH insulin injection and also a REGULAR insulin injection before I eat breakfast.  If  I start eating  my breakfast immediately after taking the injections the chances are that my blood sugar  levels will rise way  before the REGULAR insulin begins to work – especially if I eat too much quick acting carbohydrates (a few crackers).  Despite the fact that the onset of the regular insulin is a 1/2 hour to 45 minutes  – the peak performance is only after 2 hours which might allow  blood sugar levels to go up considerably   before the regular insulin brings it down.  Eventually the REGULAR insulin will of course  lower the morning pop in blood sugar — but only after what could be considered a seesawing effect depending on when and  what I ate.

Next possible problem — the NPH insulin would start to reach it’s peak (for me) about noon time which is around 4 hours after I would  take my morning injection.  In addition to this –  the regular insulin would still be working during the time the NPH  insulin started  it’s peak — making the NPH even more potent.  What this meant  is that if the regular insulin  had  brought down my blood sugar levels before lunch– the NPH plus the added effects of the still working regular insulin  had  a pretty high chance of  giving me hypoglycemia(low blood sugar) around lunch time  unless I  would eat on time – which is something I would always have to do.    In order to prevent the very unpleasant  and very scary complications of hypoglycemia eating on time became a necessity and urgent — and skipping meals would become very dangerous.

In the evening  it again becomes  necessary to take an injection of  regular insulin to bring down the rise in blood sugar from eating dinner. The peak effects of the morning NPH injection usually  ended by the evening   – so the regular insulin injection was mandatory to lower the rise in blood sugar levels from my dinner.  Again eating on time and not missing the meal is a major consideration.

As you can see – LEARNING THE INSULIN Curves is very important for all insulins any diabetic might be taking.  Not knowing the curves can be dangerous since missing or eating at the WRONG times could cause all sorts of fluctuations is blood sugar levels.

ON THE BRIGHT SIDE new insulin types have made life a lot less demanding and challenging for diabetics….

Advances in insulin have come a long way since I first got the disease.  Today my insulin regime has given me tremendous  freedom which I didn’t have in the past. I now take the following 2 insulins which have curves that have made life a lot simpler and given me almost entire freedom ovcr the times I need to eat or do exercise which was almost impossible with the insulins I used to take in the past.

1. Lispro or Humalog insulin —  this is similar to regular insulin only that instead of being sort of quick acting like regular insulin is the  HUMALOG INSULIN   is VERY QUICK acting which can help attain much better blood sugar levels!!

Onset = 15 minutes,  Peak = 30 to 90 minutes,  Duration= 3 to 5 hours

2. Lantus insulin —  this is the insulin I now take instead of NPH insulin.  While NPH can  be  considered a pretty long acting insulin (working almost a full day)  it’s peak effects  are gone after  about  1/2 a day (and the peak effects can be brutal if you don’t eat on time).  The Lantus insulin will also work around an entire day with 1 injection but there are MAJOR DIFFERENCES between NPH and lantus insulin.   The major point about Lantus insulin is that it doesn’t have a curve like the other insulins — it will work at the same potency throughout the day after the onset has started — which is very similar to the effects of an insulin pump.   To simplify what that means is that if you have a  normal blood sugar level at the time you inject the insulin then you should remain around that same blood sugar level for the entire day barring the effects of any meals or food you eat  which need to be taken care of by taking an injection of the Lispro insulin.   Maybe this doesn’t sound like much — but it is!!   Taking Lantus and Lispro instead of NPH and REGULAR insulin allows me to exercise and eat whenever I want  and I only have to remember to take the injection of Lispro  just before, during or  immediately after I eat.  The stats for Lantus insulin are:

Onset= 1 hour,  Peak = no peak ( just an equal effect throughout the day),  Duration= 20 to 26 hours

In a nutshell here’s my current regime.

Every night  – around about 7 or 8PM I take 1 injection of LANTUS insulin.   The amount needs to be enough to keep my blood sugar levels normal throughout the day barring the effects of any food I eat   during the day.  Each time I eat — be it a snack or a meal I take  a varying amount   of the lispro insulin which  brings down (on the spot more or less) any spike in my blood sugar level which would be  caused by the food I eat.  This means I do have to take much more injections per day than my previous REGULAR & NPH insulin routine  but my quality of life has improved tremendously.    Eating meals at a certain time each day to compensate for the insulin curves doesn’t really exist anymore except that you MUST NOT forget to take the lispro injection when you’ve eaten a meal – or your blood sugar levels will take off.   This can sometimes be tricky but  it’s  been worth it  to me considering the added freedom it has given me in just about every way.

Hope this post is more or less clear but feel free to comment if it isn’t.  I have no intention of changing anybodies insulin regime nor   am I trying to convince anyone what insulins  to take to achieve better control of their disease.  There will be CHALLENGES with any and all insulin regimes.    The purpose of this article is to explain the insulin curves  and to stress how important it  is that every diabetic take them into consideration……




1707total visits,1visits today


I'm a type-1 diabetic which has changed my life for what I hope is the better. My profession - at least what I get paid to do is computers (sysadmin). I'm a life long sports enthusiast and try to practise what I preach when it comes to being physically active. Still trying to achieve better diabetic control by juggling my diet, exercise and injections... As for things that interest me aside from sport -- I like keeping up on biotech research & medical devices and listening to country and western music.

Posted in diabetes control, injections, insulin

Leave a Reply

Your email address will not be published.