New to Humalog pen need help


After 2 and half years of one shot of Tresiba. It has come the time to start injecting for meals. I started two days ago injecting Humalog for meals. My question is when I prime the pen I set it at two units. I push the button and get a couple of droplets coming out. Am i doing something wrong because with a two unit prime on my tresiba pen I get a nice stream. I am starting to wonder if those droplets coming out is not sufficient for my meals. Just as an example I ate a Buona Beef cheddar croissant. Which is around 41 grams of carbs. I started with a BG of around 93. I prebolused 2 units and i spiked to 212 double arrows up on my dexcom. I had to take a 3rd unit an hour later and i walk around the neighborhood brought it back down. I just don’t know did i miss calculate? Did I time the insulin wrong or is my pen not giving me the correct dosage if i only have droplets coming out. I have the U200 Humalog pen and I leave it in the fridge. Can leaving the pen in the fridge make a difference? Or should I leave it out after opening?

If your typical dose is 2 units and it takes 2 units to prime the pen each time, then you are wasting half the insulin in priming.

If you are using the super skinny pen needles then yes you would typically get a stream rather a dribble for a 2 unit prime.

Officially a humalog vial/cartridge is only good for 28 days after you start using it. I think you can get more time if you keep in the fridge but that’s not official.

If you are only using, say, less than 10 units a day of humalog in tiny 2 unit doses, it’s possible a U-100 pen would make more economic sense than a U-200 pen. And it would also give you more fine control over the doses.

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This honestly just sounds like a very difficult meal to eat. How early did you prebolus for it? Are you sure your carb ratio is correct? It also sounds like a meal that will hit you fast but will spike you later as well from the fat/protein and require more insulin later on. Also did you eat this in the morning? That makes it even more difficult as you will have dawn phenomenon to contend with. I basically have to flood my system with insulin to get through the morning and anything I eat will have a million times the effect it will later in the day. Maybe start with something simpler like 2 pieces of toast with butter and see what happens.

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I looked up the Buona Beef cheddar croissant because I’m procrastinating doing work. It has 28g of fat and 30g of protein. This is an extremely difficult meal to bolus for, and it’s not surprising taking 2 units of Humalog didn’t do it. It’s very unlikely your pen is the problem. It is the type of meal that requires a lot of insulin up front for the initial spike, and then more later as the high fat content causes the digestion to be delayed and carbs to hit you after the initial bolus is wearing off, and some of the high protein content will convert to carbs causing you to need even more insulin. I also find anything from a restaurant is always hard, no matter what the carbs are. I’m no low carber myself, I definitely eat stuff like this, but it’s not as simple as just taking insulin according to a carb ratio and eating like some medical practitioners will tell you.

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I ate this in the afternoon around 3pm. I prebolused 2 units 15 minutes prior to eating. 1 unit an hour after when I say it rising so quick.

Looks like you may need a bit longer prebolus for something like this. Since you’re just recently starting injections for meals, there’s going to be a long trial & error period. It will take time to experiment with different foods and carb/protein/fat combinations before you can expect your doses to line up exactly as expected (or in the same range).

I’d suggest refining your dose for foods with a known amount of carbohydrates that you eat regularly. Then explore a bit more from there. Certainly eat out as much as you want, but you may want to adjust your expectations for those meals because it’s going to take time before a meal as complicated as this one works out as expected.

As @Scott_Eric said, this type of meal is more challenging to dose for. It poses all the following questions:

  • How long in advance should I bolus? Will the protein/fat delay the carb digestion?
  • If the carbs are delayed, will I drop low while waiting for the digestion?
  • If the carbs are delayed, should I bolus again an hour later?
  • If not delayed, will the amount of time I prebolused be sufficient?
  • If not delayed and my prebolus time was insufficient, how much additional insulin should I give? When should I give it?
  • Will some of the protein/fat convert into carbs? If so, when should I dose for this?

Lots of questions. You’ll figure it all out, but don’t expect things to work perfectly within the first few days.

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Remember 15 minutes is just a guideline, you could need 45 minutes to an hour for a meal like this, and/or you might need more than 2 units. You probably needed at least 1 units an hour or 2 after eating, this isn’t unexpected. Also remember it is much harder to bring blood sugar down once it is high and might take more insulin. Lastly, try Fiasp if you can. It is newer and faster acting than Humalog.

Here I have a screenshot of my dexcom. The green market to the left is my 2 unit prebolus. The food hit me pretty quick. The funny thing is I at this same sandwich last week and did not have this type of peak. I did jump on the elliptical to slow down the bg last week after eating that sandwich.

Were you using Humalog last week? Maybe starting fast-acting insulin has some effect on post-meal spikes. I don’t have LADA, but maybe someone who does can chime in.

No. Just 28 units of tresiba basal insulin.

You are still producing insulin, but I imagine your natural production is starting to deplete given that you now use insulin for meals and even when doing so had a tougher time with this meal. I was never able to rely on basal insulin alone, but used very little rapid in my first few years after diagnosis and was almost always in range, no matter what I ate. Unfortunately the honeymoon ends, and it will get worse from here on out I’m afraid.

I know you’re worried about that one spike, but other than that, wow, such a nice flat line! Congrats on excellent control!


Thank you. I am just trying to understand. I know I won’t get it this overnight, but I know many of you here have a ton of knowledge. Just want to get as much info so I can make educated decisions.

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I have had LADA for over four years now, taking Novolog for about three years and I’m STILL trying to get it right. Now I have a Freestyle Libre to help. So much OJT! Keep your chin up!

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