Monday 29 June 2020

“A Little bit More” - it's all about the Bolus



It’s been a while since I posted anything about diabetes; there’s been a veritable pandemic of words and opinions throughout the Coronavirus emergency, and I have many times in recent months turned off the TV, closed or muted a person or a conversation on Twitter or just cut short a real life conversation because I am so exasperated by a surfeit of half-baked opinion.  I am, therefore, cautious to write and post anything, let alone anything medical, but if you’ll bear with me on this one, it will get to diabetes and has no direct relevance to COVID-19. 

The train of thought leading to this post started with one of the many really bad flare-ups of hay fever which I have experienced this year. Apparently, like nearly everything, the exceptionally bad hay fever experienced by many of us in 2020 can be traced back to COVID-19, in that the (very welcome) lowering of pollution, caused by the lack of road traffic, caused by the lockdown, caused by the COVID-19 pandemic, has allowed the pollen to run riot in the less polluted atmosphere. Such is the chaos theory in practice that we have all experienced this year.

Sodium Cromoglicate eye drops
I tweeted something about bad hay fever a couple of weeks ago, and was grateful to receive much sympathy and helpful advice from friends and strangers alike. Among the suggestions was that I should try antihistamine eye drops containing Sodium Cromoglicate, a mast cell stabiliser; I had previously used standard eye drops, which provide only symptomatic relief for itchy eyes. I bought some drops of the suggested type, started using them and found that not only did they relieve the itchy eyes which are such a distressing part of hay fever, but that they also suppressed other hay fever symptoms, in particular sneezing.

This made me take to Dr Google: do eye drops enter the bloodstream and therefore act on symptoms other than the eyes themselves? I was aware, from all the COVID-19 “don’t touch your face” talk, that the eyes are a potential entry route for infections, so perhaps I shouldn’t have been surprised to find, quite readily, that the eyes are indeed a route into the bloodstream:


“When you put drops in your eye, the drops can become “pumped” into the tear system if you blink. Once in contact with the vascular nasal mucosa, relatively rapid absorption of drugs into the bloodstream can occur. The drops can act as a systemic “bolus” - an infusion of the drug into the bloodstream.”[1]

There you are - I said I’d get to diabetes! The word “bolus” jumped out of that sentence from a medical website, and - perhaps like many not medically qualified people - I was surprised to see it, apparently in a new context. “Bolus” is a word all too familiar to those of us whose lives are sustained by insulin, so familiar that I had never really thought much about any wider use of the word. However, look up the word and you’ll find a definition such as this:

“a single, relatively large, quantity of a substance, usually one intended for therapeutic use, such as a bolus dose of a drug injected intravenously.”

So it’s not just we people with diabetes who bolus! I hope that other non-HCP readers will react in the same way, otherwise this blog post is an embarrassing confession of ignorance.

Being a linguist by trade, my reaction to having a word brought to my attention is to think about and research its etymology. So again, I turned to the internet to discover that the word bolus is, as expected, of Greek via Latin origin and originally meant a clod or lump of earth. Some sources suggest a connection to the English word ball, but that is far from clear.

So there you have it: that familiar word bolus is so called because we are injecting or pumping a “lump” of insulin into our bodies. It gets even better if you know the etymology of the word “dose”, because that word actually comes from the Greek word for “gift”. I love the idea - especially as it was gifted, not monetised, by Banting et al - that we inject a gifted clod of insulin!

So what about bolusing? Well for me, it is one of the arts of diabetes management at which I have become increasingly skilled, but at which I am still a long way from being proficient, and never will be. I, along with the vast majority of people with Type One diabetes, rely on injection pens for the administration of insulin (I am miles away from fulfilling any criteria for a pump), so bolusing remains for me a relatively unsophisticated - dare I say hit and miss - process of trying to whack the mole, ideally before the mole pops up. (...now where did that “whack-a-mole" analogy come from??)

I make no claim to being an expert in diabetes; quite the reverse, in fact, compared to many whom I have come to know through the online diabetes community, but I have certainly become more confident in the art of effective bolusing in recent years.

For me, two aspects of bolusing stand out.

Firstly, the timing of bolus injections of fast-acting insulin prior to eating: I was taught at diagnosis, nearly 23 years ago, that the injection of fast-acting should be just before eating (“wait until the food is on the table”) and for years I feared some kind of humiliating loss of sense and dignity if my food was delayed for more than a few minutes. However, in recent years, I have realised that for me, a bolus dose is most effective if taken well in advance - sometimes up to an hour, especially at breakfast time.

Secondly, correction doses: I used to be very cautious about injecting between meals, but these days, I willingly inject in response to a rising level, or ahead of a snack-attack. The result of this is that I almost always have more than the theoretical three doses of fast-acting a day.

I will add two very important caveats to this. Firstly that freedom to bolus with such relative recklessness is dependent on always wearing some form of CGM, which for me is the NHS funded Freestyle Libre. I have said it many times, but the ability to know more than just a snapshot BG value, but rather a clear indication of direction of travel, is life-changing. Secondly, that I am fortunate enough to be retired and therefore more in control of my time and activities than someone in a busy working life. When I was working, there wasn’t time to pre-bolus or correct, nor was the timing or nature of my midday meal in any way predictable.

I am well aware that my mastery of bolusing will never be perfect, and indeed that it could be far better with the help of an insulin pump and associated looping technology, but I am nevertheless grateful to the incremental improvement of knowledge gained through the online diabetes community, a better-late-than-never DAFNE course and of course the advice of  HCPs.

And having discovered the etymology of bolus, I am most grateful that I am able to indulge in bit of constructive mud-slinging – throwing a little bit more insulin into my body. There’s the customary song title for my post, a memory for those old enough to remember it, from that long, hot summer of 1976.

DISCLAIMER: Injecting insulin is a responsibility placed upon everyone who lives with Type One diabetes, and requires knowledge and caution. Nobody should modify dosage and timing without careful consideration of all the multiple factors affecting blood sugar levels and any changes to the timing and dosage should only be made with professional advice and guidance.

Go Your Own Way

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