I'm not a medicine person (and not a chemist), and the question is mostly theoretical.

I've been thinking about how and why glucose and insulin are used and hwo they work, and I have several questions:

1) Would insulin and glucose react in a container?

From what I've found, they probably shouldn't, but googling is a bit difficult, as most results are about how they work together inside an organism.

2) Can an injection containing both insulin and glucose be used for rapid energy regain in case of physical exhaustion?

Here's what I found so far:

IV Glucose solution is used in china for energy regain, but actually has same effect as drinking sweet water (can be administered if drinking isn't posible though).

There's been some research of use glucose together with insulin for ketotic cows (looks promising, though there were only 12 cows in the experiment). https://www.ncbi.nlm.nih.gov/pubmed/8436669

IV Glucose solutions are usually 5 or 10 percent (at least what I found), and it's mostly used for drips, not injections (sorry if I messed with terms, but I hope you'll understand). As far as I understand that's because injecting too much glucose too fast would be bad (lead to hyperglycemia?). This leads to the next question:

3) If glucose is administered together with insulin, could it be done as an injection and with a higher concentration?

I'm sorry if those are newbie questions and anyone who's been to any kind of medical school knows the answer. I've tried googling in different ways, but couldn't find an answer.

UPD: I am totally NOT going to inject anyone with anything. I'm writing a book and need to know if this could work (after thorough calculations and tests and everything).

UPD 2. Some details of the story:

There are people who can go berserk (and be stronger, faster, etc than usually). The effect is similar an adrenalin rush, but can last for a while and can be induced and cancelled at will (after some training). Physiologically these berserks are no different from regular people (or at least not in a way detectable by modern medicine). My guess for now is that they just somehow can control (at least partially) existing system of stress response.

This berserk state drains energy a lot (yeah, the description would match worldbuilding.se better, that is why I didn't want to post it here) and it's crucial to restore energy as quickly as possible after. My idea is that you can inject 50% (or maybe even more) glucose solution, but I doubt you could drink it, so volume is much less, which is good. Also, if something didn't go exactly as expected, the berserk might pass out on exiting the berserk state, then drinkable treatment is definitely not an option.

For sure, the treatment is complex and contains other things that need restoring. It might be not glucose+insulin, but I thought it might be an interesting solution, as it allows creating substitute treatment given access to any drug store.

Total misunderstanding of human physiology might also be the case. Then I'm sorry to have bothered you.

  • Actually, a 50% glucose solution is commonly used emergently to treat hypoglycemia. It is injected intravenously.
    – Carey Gregory
    Commented Apr 16, 2019 at 0:45
  • @Alissa, even if it works, it is not practical, because it is dangerous even when a doctor in a hospital does it. And they injected only insulin. I have not found any case in which they would inject both glucose and insulin.
    – Jan
    Commented Apr 17, 2019 at 9:30
  • @Jan insulin-only is dangerous, yes, but it doesn't mean the mix is also dangerous (assuming tests and calculations were done beforehand). And yes, I also googled and looks like no one has ever done that, but that doesn't mean it couldn't be used. If I'd found cases when someone tried that, I probably wouldn't ask here
    – Alissa
    Commented Apr 17, 2019 at 9:48
  • We all here have the same issue - I haven't found a single study that would use both glucose and insulin. Without actual studies we can only speculate, because this can't be just calculated. Every person has at a certain moment a certain amount of glucose in the blood and a certain amount of insulin naturally secreted from the pancreas, which differs from time to time and from person to person. So, you can't determine a certain dose of glucose and insulin in the injection that would be safe for all.
    – Jan
    Commented Apr 17, 2019 at 10:22
  • @Jan, but could it be some personal treatment? E.g. If we determine all that for one person, could we create such personal shots? As I mentioned, that's for a book, and need to calculate stuff for each person is ok, if it would look plausible.
    – Alissa
    Commented Apr 17, 2019 at 14:32

1 Answer 1


Glucose and insulin could co-exist in the same container without reacting.

Intravenous insulin has been used to treat hyperglycemia. There is a risk of severe hypoglycemia and even death after intravenous insulin (Diabetes Spectrum), which makes it inappropriate for use outside hospitals.

What naturally happens during stressful physical work?

Stress triggers the adrenal glands to release the hormones adrenaline and cortisol, which break down glycogen (in the liver and muscles) into glucose, and fats into fatty acids, which then appear in the blood. This triggers the pancreas to release the hormone insulin, which stimulates the entrance of glucose and fatty acids into the muscles thus providing substrate that can be broken down into energy. Adrenaline stimulates this breakdown. Adrenaline also dilates the bronchi in the lungs thus enabling more oxygen to enter the blood. It also dilates the arteries in the muscles thus increasing the blood flow and hence the delivery of oxygen and nutrients to the muscles.

So, insulin merely enables glucose to enter the cells, but they are adrenaline and cortisol that enable the release of energy (energy boost).

What is exhaustion?

Simply put, exhaustion after physical work is lack of energy, mainly due to depleted glycogen stores (the source of glucose) in the liver and muscles.

Without glycogen, one would be much less able to run fast and fight.

How to naturally replenish glycogen stores?

Having several high-carbohydrate meals provides glucose that appears in the blood. This triggers the release of insulin, which stimulates the entrance of glucose into the cells. Glucose that is not needed for the energy at the time is used to replenish glycogen stores - this process is also stimulated by insulin. This way, glycogen stores can be fully replenished in about 24 hours (PubMed, 2018).

Glycogen replenishment is optimal when one starts to consume carbohydrates immediately after exercise. If the consumption is delayed for 2 hours, glycogen synthesis can be reduced by 50% (Today's Dietitian). This also very likely applies to glucose injection.

The optimal amount of carbohydrates is 0.6 g per kg of body weight every 30 minutes, so, for a 70 kg person about 40 g carbohydrates every 30 minutes for four hours (up to 700 g per day) (PubMed, 2018).

How could glycogen replenishment be artificially accelerated? (pure theory, not proven effective or safe)

According to one study, intravenous glucose stimulates glycogen synthesis, but there is no timing mentioned.

Fructose and galactose injection can result in twice as quick glycogen synthesis as a glucose injection (PubMed, Diabetes).

Concluding from the following article (PubMed, 1991), insulin by injection might not stimulate glucose uptake by the liver and hence glycogen synthesis beyond the rate already achieved by naturally secreted insulin.

Experiments carried out in man have suggested that insulin may play only a permissive role in the determination of splanchnic glucose uptake. In a study by DeFronzo et al. (5), in which the plasma glucose and insulin levels were raised via peripheral intravenous infusion to 223 mg/dl and 55 μU/ml, respectively, net splanchnic glucose uptake was 1.0 mg/kg per min. The rate of glucose uptake did not change appreciably when the arterial insulin level was raised further to 191 μU/ml.

Here you can see that, as a natural response, insulin levels can reach 276 μU/ml 1 hour after glucose administration.


Theoretically, it seems that the optimal recovery (glycogen replenishment) after exhaustion could be achieved by injections of a mixture of glucose + fructose, at the rate 0.6 g per kg body weight, starting immediately after exercise and repeated every 30 minutes for 4 hours. Full glycogen replenishment in a 70 kg person might require 700 g of the mentioned carbohydrates per day. Some transient hyperglycemia could occur this way, but this would be likely without symptoms. 70% glucose (dextrose) solutions are available.

Intravenous insulin might not stimulate glycogen synthesis significantly more than naturally secreted insulin. Intravenous insulin injections would also require constant measurements of blood glucose levels to avoid hypoglycemia.

  • 2
    I actually know of a fatal case of IV insulin usage to treat hyperglycemia. The (inexperienced) ED doctor reasoned that given the patient's very high sugar level a larger dose of insulin should be used. The resulting brain swelling killed the patient.
    – Carey Gregory
    Commented Apr 16, 2019 at 0:48
  • I know that insulin causes hypoglycemia. My thought was that if one uses IV glucose, it will only have effect after body finds out that there's some extra glucose and produces some insulin. So, in theory, if injection contains both glucose and insulin, thise gap could be removed. Or not?
    – Alissa
    Commented Apr 17, 2019 at 9:16
  • Insulin is usually administered subcutaneously and it is released into the blood slowly. Intravenous insulin has much quicker and stronger effect.
    – Jan
    Commented Apr 17, 2019 at 9:17

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