Optimum fluid volume / insulin dilution?

[ratatoskr]

I wonder what is the optimum insulin dilution or volume to get the best absorption to the blood/body? This apply to both pen and pump users.

Say you need a 5U bolus after a meal.
With U-500 the volume is 0,025ml.
With U-100 the volume is 0,05ml.
With U-50 the volume is 0,25ml
and with U-10 the volume is 0,5ml.


Too small volumes makes it difficult to give an accurate dose, or increased risk of clogged infusion sets.

Too grate volumes is supposed to increase the risk of getting "pockets" of insulin under the skin which the body will absorb at an uneven rate.

Some pen and pumps can only handle U-100 insulin, others can handle thiner dilutions.


Do anyone of you know of any studies at this subject, or is it basic knowledge for any doctor?

I'm thankful for any thoughts, experiences or opinions.

[lark 27]

I've got no studies for you, but it's an interesting question. I'm going to blindly trust the medical establishment on this one that has chosen to go with u-100 as the typical dilution at least here in the U.S. Of course trusting the medical establishment can get a person in trouble, but it doesn't seem like it would be worth the effort to me to try to convince my Doc to prescribe a u-500 or something like that. Of course for others with large needs, it would make some sense.

[Subby]

I can see the problems as pointed out, with too little and too great a fluid. In fact, for me, 3 units and above of u100 tend to pool (or "something" - allergic reaction?) so that absorption is very poor. I can get around it injecting in 2u doses or pumping square. So in these cases I can see specific reasons to avoid a certain amount of fluid. But normally is there a reason to believe the liquid amounts of typical doses of say u100 are going to affect absorption much? I'm not aware of a general trend - though I'm open to theories or data that suggests there is a correlation between amount and absorption. What prompted the question? Do you have suspicions that typical u100 doses are compromised by the liquid involved (water, maybe glycerin to some degree).

My thought is, regarding absorption and injections, the limitations may well be with sub-q delivery in general in most people, more than anything. My vague understanding was, it's when they work out ways to deliver safely and effectively to the portal vein or those similar regions that actually utilise the insulin the most, that absorption might suddenly become a whole new ball game.