Why is it that Type 2 Diabetes can be treated by oral medication?

wayhey

Let me point out this isn't any sort of advice-seeking. It came up in Biology today when the book said Type 1's inject directly to the bloodstream seeing as the insulin would only be broken down by the stomach cos it's a protein. Then someone pointed out Type 2s can take the meds orally, so what's the story with this?

bleg

People suffering from Type 2 Diabetes only have to use insulin in severe cases.


Insulin is a protein and like most proteins in the digestive tract it gets broken down into its constituent parts. There has yet to be a formulation that allows for oral admin of insulin (however there was an inhaled formulation on the market called Exubera.) Therefore insulin must be injected.

Type 2 can be controlled using different meds such as glitazones or biguanides which are orally active. They are absorbed from the GIT, unlike insulin.

A Wiki or google search will bring up more info if you want it.

Vorsprung

With Type 1s, you're replacing the insulin that they're unable to make. Insulin can be given intravenously (i.e. straight into the veins) but that's only done in special circumstance in hospital - people taking insulin at home take it subcutaneously, which means an injection just under the skin, usually around the abdomen.

Type 2s make insulin, but the cells upon which it acts are less sensitive to it. So you get around that in other ways, by getting the cells to make more insulin, making the cells more sensitive to insulin or by reducing the amount of glucose in your body. These other drugs are not proteins, so won't be broken down when taken orally.

mardybumbum

Oral glucose also causes a greater release of insulin than IV injection, as it stimulates the release of GI hormones which in turn stimulate the release of more insulin.

The main reason however, has been outlined above.
I think that Rang and Dale does a great job on the endocrine pancreas.
Check it out if you have the time.

KP81

Just to elaborate on specifically why insulin is not absorbed: As a protein it will be denatured in the acidic environment of the stomach before it hits the GI tract (where absorption occurs). Also, being a protein it is a hydrophilic molecule (ie water soluble) and this is not absorbed easily through the intestinal wall. Many companies have worked on trying to deliver insulin orally but no commercial product exists yet. Issues with intra patient variability and safety of chronic use of delivery agents exist.

Currently an Irish company called Merrion pharma is testing a way to deliver oral insulin analogues by bypassing the stomach using enteric coating and using a permeation enhancer to allow the drug to be absorbed. They're at phase I/II so it will be 3-5 years before anythig hits the market.

DrIndy

KP81 wrote: »

Just to elaborate on specifically why insulin is not absorbed: As a protein it will be denatured in the acidic environment of the stomach before it hits the GI tract (where absorption occurs). Also, being a protein it is a hydrophilic molecule (ie water soluble) and this is not absorbed easily through the intestinal wall. Many companies have worked on trying to deliver insulin orally but no commercial product exists yet. Issues with intra patient variability and safety of chronic use of delivery agents exist.

Currently an Irish company called Merrion pharma is testing a way to deliver oral insulin analogues by bypassing the stomach using enteric coating and using a permeation enhancer to allow the drug to be absorbed. They're at phase I/II so it will be 3-5 years before anythig hits the market.

The big issue here is how to deliver the correct amount of insulin needed for the glucose load of the body where you take the insulin hours ahead of the meal.

The potential for severe hypoglycaemic reactions and underdosing is significant indeed and undoubtedly you would still need topup injections.