Symlin/Insulin mix in pump?

I've had good results using Symlin, but have to confess that I have gotten lazy about using it. When on MDI it's two injections before meals, and when I use my Omnipod while on business travel, I find it a hassle to carry the additional pen and supplies. Hence, I usually only rely on insulin alone to manage my BG.

Then an idea crossed my mind: What about pre-mixing the insulin with the Symlin in the pump reservoir? Getting precise ratios would not be a problem because one could inject exact doses of each into the reservoir from pens.

Have any of you ever experimented with this and been successful?



Wow! I hope your kidding...I don't think Symlin was meant to be pumped around the clock in a insulin pump. Just how do you intend to keep it from mixing with the basal portion of insulin that's in the pump?????

No John, I'm completely serious. Of course Symlin was not originally intended for a pump, but if we were all doing exactly as told and not challenging the status-quo, imagine the state of diabetes therapy today. Hence my post. I'm wondering what effect, if any, a continued small basal delivery of Symlin would have. Alternatively, one can also solve for this by injecting basal and using the pump symlin/insulin mix only for boluses. I'm curious if anyone has experimented with this and what the results were.

Why don't you try and lets us know how if works out (after the hospital stay).

Without even think I can come up with several reasons this is a horrible idea.

I'll post just one:

Never mix SYMLIN and insulin. Insulin can affect SYMLIN when the two are mixed

From the FDA Medication Guide.

Also, this is a completely false statement:

Getting precise ratios would not be a problem because one could inject exact doses of each into the reservoir from pens.

Discounting the aforementioned prohibition, how would you insure a homogeneous mixture of the two in the reservoir?

Alternatively, one can also solve for this by injecting basal and using the pump symlin/insulin mix only for boluses

Completely subverting the "hassle" of carrying additional supplies.

Did not really think this through did you?

Pharmaceutical companies spend countless millions of dollars and thousands and thousands of man hours 'experimenting' on drugs. But of course you can give it a whirl.

Hey brbroyer:

Thanks for taking the time to read and respond, but I kindly ask you to re-read my question. I was asking if anyone had experimented with this, or at minimum have an empirical, adult discussion. Had I asked for a snarky, mean-spirited and condescending opinion, you would have nailed it. Granted, I am impressed with your blind faith in big pharma and your demonstrated excellent command of "cut" and "paste."


I was not sure you would be able to grasp the nature of my reply.
But I see that you did. But that does not in any way discount the information contained within.

Good for you.

I took symlin with injections for about a month and it caused nausea and hypos while I was eating so I stopped using it. I tried adjusting the doses of my insulin which didn't work, but I never got past the lowest dose of symlin. It did help my feeling of hunger, but honestly I don't think it is a good idea overall because of it slowing down the digestive tract. I also agree that I think using it in a pump would probably be dangerous and I don't think it would be possible to dose it correctly etc.

Christopher I copied this from the dosing sheet:

[• Never mix SYMLIN and insulin. Inject SYMLIN at least 2 inches away from your insulin injection site.]

I see no reason for the manufacturer to lie about it...but if you insist...;-)

Oh I got it alright, brboyer. Maybe you will grasp that your lack of civility and unprovoked, condescending and venomous posts have no place in our community, and such continued behavior will not be tolerated here.

It may have been a little condescending, deservedly so, but it was pretty civil and there was no hint of venom.

I am like Christopher and wondered why they should not be mixed so I did an internet search and found this article from A Sweet Life. it is rather lengthy but you can find it here.

From what I gather reading this article is that Symlin when added to insulin alters the pH properties of insulin which allows the insulin molecules to bind together and form a white powder for which then falls out of the solution making the insulin useless.


In short, let me answer your question - NO. Do not mix the two.

That said, there are a few people who have tried ("Google-fu found a few instances) BUT the important part is this:

A medical research paper on this very subject. In short, dont mix them.

Here is another good write up for you as well:

I was going to ask about pH interactions but I see Gary got there first. i would also wonder about simple chemical reactions between two solutions that weren't designed with each other in mind and haven't been tested together, as well as temperature issues and shelf life in a reservoir. If I were interested in being an experimental subject (which I'm not), I would still require definitive answers to questions like that, first. Some mistakes are harmless and easy to "do over". Some are not. The trick is in knowing which is which ahead of time.


For folks linking to a Sweet Life, there's a later post addressing why Karmel no longer mixes:

Great data, Gary, Dan and Shadow Dragon. This is exactly what I was looking for. Thank you!! It looks like mixing was possible under the original formulation in vials, but once they moved to pens it became no longer possible due to PH differences.

Add to that, the testing was done with syringes where the mixture was injected immediately, not with pumps where it would need to remain stable for hours or days.

This was true in the case of the AJHP study ( where they found no meaningful difference in separate or mixed injections, however Karmel Allison wrote about mixing it successfully for pumping until they changed to the more concentrated formulation available in pens only (

Again - fascinating information. It's a shame it's no longer possible.