A Practical Symlin Guide for Type 1 Diabetics - Part 1: Introduction

This will be the first of several blog posts that I have been working on for the past month, all written with the Symlin novice in mind and with the intent of encouraging as many of you as possible to start on Symlin therapy. I do not work for Amylin (makers of Symlin), or even in the pharmaceutical or health care fields. I do not own Amylin stock. I decided to write this guide because Symlin is so extraordinarily effective at mitigating some specific issues many Type 1s consistently encounter and struggle with, including post-prandial hyperglycemia, weight management, insulin dosing, and appetite control. Given its rather remarkable benefits it is also extraordinarily underused by the Type 1 population as a whole, and in my opinion this is because Amylin has not been successful in effectively communicating these benefits to Type 1s.

Please feel free to comment on my posts with criticisms or correct me if I make a mistake.

What is Symlin?

Symlin is an analog chemical that closely mimics the action of an endogenous human hormone produced by the islet cells called amylin (yes, the same name taken by Symlin’s manufacturer). The first time I read about amylin was in the mid-1990s when I picked up a heavy medical tome from my college library and looked up “islet cells”. That book mentioned amylin as something that was produced by the islet cells, but did not give me any insight as to what amylin did or why it was important to the human body. At the time, I was a newly diagnosed Type 1 and had a lot more on my plate to get used to, so I didn’t give it much thought. That was also about the time Amylin began work on bringing Symlin to market, and in 2005 Symlin became only the second drug ever approved for the treatment of Type 1 diabetes (the first of course, being insulin).

Amylin is secreted by the islet cells along with insulin in a roughly 100:1 ratio of insulin to amylin, as part of a normal human body’s reaction to food. It does not and cannot lower blood glucose on its own, but accomplishes the same through a variety of indirect means, including:

-Suppression of appetite
-Signaling the liver to stop releasing glycogen (stored sugars) into the bloodstream
-Slowing the rate at which your stomach empties, thereby significantly reducing or eliminating altogether post-meal spikes in blood glucose
-Increasing the potency of insulin

You might have guessed that eating less food and needing less insulin to cover meals might result in significant weight loss. This is true. Symlin is truly remarkable in this aspect, and in fact Amylin is in phase II clinical trials now with a combination drug treatment of Symlin and another hormone called leptin, designed specifically to treat obesity. I lost about 30lbs. on Symlin over the course of less than three months, without any other changes to my diet or exercise routine.

Human amylin can be quite toxic in that it promotes the formation of amyloid plaques throughout the body. These plaques are implicated in a host of nasty diseases, including Alzheimer’s, Parkinson’s disease, and rheumatoid arthritis. For this reason, Amylin used parts of the rat version of amylin in creating Symlin, so that it retains its positive effects in humans without the toxicity problems.

Is Symlin right for me?

Are you a human being? Do you eat food? Then Symlin is probably right for you. However, going on Symlin requires diligent attention to your diabetes and can cause some serious problems if that is not your current strategy. If you already struggle with hypoglycemia then it would be best to work that problem out before starting on Symlin, as it is the most challenging aspect of Symlin therapy. If you have hypoglycemia unawareness, Symlin is probably not right for you. I recommend using Symlin in conjunction with a CGMS as it is much easier to deal with any potential hypoglycemia that way, but I and many others acclimated to Symlin without one so it is by no means necessary.

How is Symlin taken?

Symlin is taken by injection only, immediately before a meal. The literature says to use Symlin only with meals containing 25 grams or more of carbohydrate. I have found it beneficial to use Symlin before any substantial eating, whether or not I hit that magic number. For me “substantial eating” is any volume of food that meets or exceeds a couple of bites. So, I won’t take my Symlin if I toss down a couple of crackers with cheese at a party, but anything more than that gets a jab.

It does come in a pen, like most forms of insulin, and as a pump user who hasn’t used injections since 1997, I found this much more convenient than lugging around a kit with bottles and syringes. Unlike insulin, your Symlin dose will not change- it will be either 60mcg or 120mcg per injection, no matter how much you eat. There are two pens available- one that maxes out at 60mcg and one at 120mcg. The 60mcg pen can deliver doses in 15mcg increments from 15mcg up to 60mcg. The 120mcg pen can only deliver 60mcg or 120mcg per injection. I will discuss dosing in more detail in the next post, including how to acclimate to your full dose of 60 or 120, and how it reduces your meal-time insulin requirement.

Symlin cannot be mixed with insulin for injection, nor can it be infused with insulin in a pump. A few brave souls have hooked up a second pump to infuse Symlin, but I believe the pen and consistent dosages obviate the need for such an expensive and inconvenient method.

What are the negative side effects?

After you have acclimated to your full dose, there are surprisingly few, if any at all. I experience no negative side effects myself and I have been using Symlin since September of 2008. During acclimation, you may experience some mild to moderate nausea and gastric discomfort for a short while after eating. And while this is not a true side effect of the medication, I would be doing you a great disservice if I did not mention that the pH of Symlin is apparently rather low and it does not appear to be buffered much. So unlike insulin, which goes in painlessly, Symlin can sting a bit at doses at and above 60mcg. Some have mentioned they don’t notice it at 60mcg, so your mileage may vary. I have in the past compared the 120mcg dose to injecting lemon juice but I am being a tad hyperbolic. Nevertheless, be prepared, but don’t be scared. It is quite tolerable, especially for anyone used to the sharp snap of an infusion set or CGMS insertion.

I also use my abdomen almost exclusively, but I have noticed it stings far less in my leg or butt. Absorption does not appear to be effected by where I inject, so this may be a good way to mitigate the pain if that is an issue for you.

That’s enough for my opener. Part 2 will cover acclimation in more detail, hypoglycemia issues, and meal bolus strategies. Part 3 is still a work in progress but thus far contains information on exercise, missing Symlin doses, potential train wrecks, and more. If you have any suggestions please send them my way. Thanks and good luck!

1 Like

Excellent post! Thanks, just started using it myself.

Appreciate the comprehensiveness here, looking forward to the next installments.

Good job Scott. I’ve been on the 120 mcg dose as a type 1.5 for about 3 months now. It works well for morning meals, and sometimes too well for my lunch and dinner meals. I’ve had to lower my lunch and dinner insulin ratios significantly (50%) as recommended in the labeling. But that’s a good thing. I haven’t lost any weight, but then i dont’ really need to. Looking forward to your next post.

Thanks for telling me about this!..Great blog,cant wait for the rest!

I don’t know Symlin and I want to ask a question: is it good for thin diabetic type 1 with high blood sugar after meal?

Well, Symlin is taken with meals and seems to get out of the body pretty rapidly, so the times you would normally be correcting would be times that symlin wouldn’t be in your body. If your body is still sensitive to insulin, you may not need symlin, tho it would probably reduce the amount of bolus you take with meal. It will cut your appetite tho. In my case, it made me feel “very” full. Not the full where, “oh I can squeeze in a couple more bites” but the full where “one more bite and I’m gonna hurl”. So I did eat a lot less volume. If you are thin, weight loss could be a concern.

It did help me DRAMATICALLY with my post meal highs. I literally could not get a bolus out of my pump that was large enough to cover a meal. I would regularly hit 2hr numbers over 250. With the symlin, my 2hr numbers were usually below 150. A few times, when I was on that sample, my 2hr meal would be right in range. And just when I was getting everything all figured out with it, my sample ran out. Now I’m arguing with my insurance company about whether I need it or not.

having my 2hr number be better allowed me to actually get my basal rates correct. And that is what you have to have to really be successful at pumping.

For all the reasons stated, Symlin is not a appropriate therapy for all Type I’s. You have to know what you are doing when using it. It’s not for beginners either. For those of us with insulin resistance who continue to spike after meals, it is a good alternative therapy. Take a minute to go to the Symlin website and read about the indications and containdications for use. The weight loss is just a side effect. Like i said, I’ve not lost any weight, but I don’t need (or want) to either. I’m just very insulin resistant. Symlin works very well for me.

thank you. I’ll ask my endo next week. And I’ll go to see the website.

Arielle-

Please take a look at Part 2, where I do cover the issue of hypoglycemia in depth. There are ways to bolus that will minimize the risk, but it is true that using Symlin requires more attention to your diabetes. That extra investment however pays off very large dividends.

Glucagon is not rendered useless by Symlin anymore than it is rendered useless by insulin, which works to move your blood glucose in the opposite direction. Symlin cannot lower blood glucose on its own. In my experience, the correction boluses aren’t affected nearly as much as your meal boluses are with regards to insulin sensitivity.

I don’t see why you could not correct as you do now- you can experiment with a half unit and see how it goes. Symlin is out of your system relatively quickly- the half-life is approximately 45 minutes.

With regards to weight loss, Symlin is very dose-dependent. I did not experience nearly the level of weight loss at 60mcg as I did at 120mcg. I believe my total weight loss at the 60mcg level was 5lbs. or less. This is primarily due to the appetite suppression, and if you already eat small portions you may, like David, not notice any weight loss at all with the 60mcg dose. I can’t imagine that being true at 120mcg- there are some times when I don’t even need a bolus for my meal (relatively rare and dependent on a few other factors).

I would agree that Symlin isn’t for everyone- people who do not pay close attention to their diabetes or are unwilling to invest the time and effort Symlin therapy demands should not use the drug because that combination could and probably would lead to dangerous hypoglycemia. Outside of that, it is my opinion (and you of course are free to disagree) that every Type 1 should be replacing this hormone just as they replace insulin.

Thanks for the feedback!

This is extremely interesting. The first time I heard of if. Do you think that a child in puberty can also use is - since puberty cause a natural resistence to insulin? (Please post the link to part 2)

To read part 2, click here.

great job!! that is how i found tudiabetes = i wanted to know about symlin. i started 8 months ago. my dr said i could mix the symlin w/ my novalog or my levemir. is that not right?

You cannot mix the Symlin in the same syringe as insulin. You can take Symlin as a separate injection along with an injection of insulin.

you talk about 120 mcg. i take 20 units of symlin 3 times a day. how does that calculate w/ the mcg thing.?? thanks for all this info. i have lost 7 lbs but that wasnt until i changed from lantus to levimer. im still not sure of the benefits even after more than 8 months.

i am a new symlin user (on a pump - have had diabetes for 52 years). i have had none of the “bad” symlin experiences and am now taking 60 units whenever i eat 25 grams of carbs. i have several questions. i am a grazer and don’t frequently eat 25 gr in one sitting. also, my doctor says that 60 units of symlin is the most any type 1 should take. (that a 120 unit regimen is only for type 2’s). any suggestions? should i go ahead and take 60 units when i eat 15 gr carbs? i haven’t lost any weight (after 1 1/2 months) and that is why my dr. prescribed it for me. also - what about the 120 unit/60 unit - type 1 limit? many thanks!!

Realize that these are based on the label recommendations for amylin and these were largely implemented based on the past experience of the primary amylin reviewer assigned to Symlin at the FDA, Dr. Robert Misbin who had experience with another FDA type 2 drug called Rezulin and was being extremely cautious, not because amylin was inherently any more dangerous than using insulin alone – that’s an office politics decision as far as I’m concerned, but was not based on solid scientific evidence. You can catch my post on this subject in the Symlin User’s Forum HERE for some of the sordid background on that. The reason I mention this is because I met someone who had hypoglycemia unawareness and used Symlin very successfully, largely because his total daily dosage of insulin was reduced rather significantly, which his endo believes reduced his incidence of hypoglycemia (amylin cannot cause hypoglycemia, insulin does). He did use it with a CGMS, but the reliability of these devices remain problematic, but at least they can alert that blood glucose levels are falling in patients who cannot sense these based on traditional symptoms.

Jason,
I posted your practical guide to symlin part 1 on the insulin pumpers list. I hope this is OK. I acknowledged it with your first name,and the fact that it came from Tu Diabetes. there is so very little information out there about symlin. Yours were the best comments I could find. I think the stuff is amazing and I don’t know why more type 1’s aren’t using it. Thanks.

No problem, Maureen. Thank you!