Understanding Novolog

blondy2061h, MSN, RN · Sep 18, 2008

Novolog is a fast acting insulin- faster than Regular with an onset of 15 minutes, a peak in an hour, and a duration around 4 hours.

It sounds like the 6 units was meant to cover the food being eaten, while the 2 units was a correction for the 123 to get it closer to an ideal fasting bg of 90.

This patient probably had some level of insulin resistance, but I would have no problem giving that dose. Doses vary so much from person to person you need to base if a dose is appropriate based on their norm, not what you've seen in other people.

dansingrn · Sep 18, 2008

The Novolog dose was likely ordered to cover the amount of carbohydrate in the meal. It is not based on the current blood glucose level. In other words, the dose is calculated in proportion to the carb content. If the patient were going to consume a lot of carb, the dose would be even higher, irrespective of the current BG of 123.

The interesting thing is that the patient had an order for both Humalog and Novolog - both are rapid acting insulins. They are used in exactly the same manner, just made by different manufacturers. It is a little unusual to be taking both. Technically, Humalog has a faster onset and shorter duration than does Novolog, but only slightly. Humalog/Novolog are usually used along with a long acting insulin such as Lantus or Levemir.

blondy2061h, MSN, RN · Sep 18, 2008

I didn't catch that the OP said Novolog and Humalog. Are you sure the set dose wasn't Humulin N or something? I wouldn't think many hospitals would have both Humalog and Novolog as formulary.

dansingrn · Sep 18, 2008

Oops, I meant to say that the 6 units Humalog was to cover the meal. The additional 2 units Novolog was written as "algorithm" per the OP. Either way, still not sure why they are on both.

IngyRN · Sep 19, 2008

Thanks for the replies. The pt was actually just on Novolog ( apparently I was sleepy when I started the thread-sorry). The patient initially had very high BS despite being on a high dose algorithm (250 to 370's), so they added the prandial dose. After this, the BS were improved ranging 140's to low 200's. I realize Novolog is fast acting- I was afraid he would bottom out with 8 units. For my own knowledge, how do I know when it;s too much insulin and should question the order-are there any resources you can offer. I feel pretty clueless about it all.

dansingrn · Sep 19, 2008

You could use the "1800 rule" as a guide to give you a reference point. Of course, this would just be for your peace of mind or a rationale if you felt you needed to verify the order with the provider who wrote the order.

http://www.diabetesnet.com/diabetes_control_tips/corr_factor.php

1800/TDD (total daily dose) = how many points one unit of Humalog/Novolog can be expected to drop the blood glucose.

The accuracy of this rule varies by individual. It works very well in most cases, especially if the amount of long acting insulin (Lantus, Levemir) or intermediate acting insulin (NPH) taken daily is approximately 50% of the total daily insulin dose.

To figure TDD, add the long or intermediate acting dose to all the rapid or short acting doses taken through the day. This number will vary if the patient uses an insulin to carb ratio to vary the dose with each meal, but a "most common dose" estimate works just fine.

blondy2061h, MSN, RN · Sep 19, 2008

The 1800 rule is a good starting point, but doses can still range so widely from person to person. I would compare the doses to what he's been getting and his previous blood sugars, and see if it seems appropriate. If the patient had 8 units yesterday and had good blood sugars, you know it's appropriate. If the patient has been having lows on 4 units, you should probably question the order.

classicdame, MSN, EdD · Sep 21, 2008

a lot of MD's in my facility order 1:15 or 1 unit of Novolog to every 15 grams of carbohydrate. It sometimes the ratio differs, but the idea is that the dose is to cover the meal only. NPH or Long-acting like Levimir or Lantus is usually added to serve as basal dose. If the patient is getting fast acting only I assume there is an oral med or strict diet and history of compliance.

blondy2061h, MSN, RN · Sep 22, 2008

a lot of MD's in my facility order 1:15 or 1 unit of Novolog to every 15 grams of carbohydrate. It sometimes the ratio differs, but the idea is that the dose is to cover the meal only. NPH or Long-acting like Levimir or Lantus is usually added to serve as basal dose. If the patient is getting fast acting only I assume there is an oral med or strict diet and history of compliance.

That's great to hear about doctors prescribing carb ratios in hospitals. Very progressive of them. Does nutrition provide the carb count for the meal?

dansingrn · Sep 22, 2008

Our hospital has "room service" type menus. Kids order whatever they want from the menu when they are ready to eat. (No ready-made trays brought at a certain time!) Our menus have the carb content of every single item right on the menu, so they can be added right up for calculating the dose per the ratio.