How much premeal humalog

If my BS premeal are 200 and I have a meal of say 30 CHO with CHO insulin ratio 1:30, should I add more due to beginning # high?

Ideally you want to take a total amount of insulin that is equal to a bolus according to your carb ratio combined with a correction according to your correction ratio. Remember these things aren’t static though, and there are a billion variables to keep in mind. The most important is the higher you are, the more insulin you need. This means that a carb or correction ratio that typically works for you when your blood sugar is 150 might not give you enough insulin when your blood sugar is 200 or 250 for example. Also the type of carbs matter too, and also whether your blood sugar is stable at 200 or increasing or decreasing. The amount and timing of insulin will be different for very fast-acting vs. slow-digesting carbs, and it gets messy when foods have combinations of both, or you are bolusing for dessert after a meal when your stomach is full and the dessert won’t digest as quickly. Carb counting is inexact, tricky and requires a lot of trial and error.


Check with your medical care professionals for insulin dosing.

The short answer is YES. You have to do a correction according to your correction factor. Then figure out how many carbs you are planning to consume and bolus for that according to your insulin-to-carb factor, which you say is 1:30 and following the guidelines that Scott alluded to.


Agreed. Nice quick summary.

I also agree with Scott_Eric and Tim35.

Two things you need to know:

  1. What is your carb coverage ratio?
  2. What is your correction factor?

My provider and I used the “Rule of 500” as a starting point for figuring out the carb coverage ratio and the “Rule of 1800” as the starting point for figuring out the correction factor. Most helpful calculation explanation:

Personally, I need more insulin in the morning to cover carbs and less after midday. Food types also can impact the coverage needed. One of the best things you can do is track your food and insulin dosage plus your glucose readings before and after meals to understand how your body responds and stay on track. If you are high going into a meal, you will need to adjust your insulin dose to both correct for the high and to cover carbs. I use the MySugr app although there are numerous apps that do a good job. The key is tracking consistently and sharing your reports with your doctor.

Good luck.


If that thing says 200 the last thing I am doing is eating carbohydrates. That would be like adding coal to a steam boiler when the pressure gauge is already in the red.


IMO if BG is 200-250 its seriously time to look BACK for the mistake that made those numbers in the first place instead of “correcting” and eating more carbs.

Exercise can drop my numbers 1 to even 3 points per minute. That thing says 200 I am out the door for a fast walk , bicycle ride or the gym. Then I think back what did I mess up to go that high ?

I am new at this and my last lesson a few weeks ago was learning that if its raining and I sit around indoors for 3 days playing computer but do everything else the same by day 3 add 60 to my usual numbers.

I learned how to manipulate insulin sensitivity with exercise and to eat so that I run on Lantus only.

They said T1 and gave me that sliding scale when I left the hospital, once I learned how eating carbs and exercise effects things Humalog was over. I am not sticking that needle for a baked potato or piece of cake.

We are all different , not saying anyone is wrong, but if I listened to them…

The OP is just asking for some basics on how carb counting and corrections work. I agree, I make different choices based on my blood sugar reading sometimes, but there are also times we all want to eat something regardless of what the number is and it’s important to know how to do that. How long have you been diagnosed? I can tell you as an experienced t1 it’s not realistic to avoid fast-acting insulin and I don’t see why you would want to.

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About 6 months into this T1.

I will never get enough enjoyment from a piece of cake or baked potato to be worth doing a needle stick. I am over the beginning horror of needle sticking but still. If I am at 70 and am going out its carbs time but @ 200 I am thinking of long term diabetes consequences not about how good a bowl of fried rice would be right now.

You’re new to this and probably honeymooning which is almost like a different disease. Hate to break it to you but even carb-free meals often require an injection. If you don’t like stabbing yourself multiple times a day a pump is the answer. Are you using pens though? Pen needles are very small and painless.


That honeymoon over… that’s likely going to suck.

I will learn to do it if and when the time comes but for now I can be bossed around by that meter. Its not that hard. We got an understanding of one another.

Thank you all for the insight. Great list we have here. I am still new to this and being a Registered Dietitian, it is difficult for me to grasp at times. Variables…yes. One week my #s are good and then out of no where they run high or low. Cant make sense of it at times. I do not have a pump and am pre-mealing insulin at this time. For those of you with a pump, recommend? Advantages, disadvantages, difficulties, concerns?