Changing Basal Rates

My question is: How many of you tweak your basal rates on your own without your endo's permission or instruction?

Here is why I'm asking...

I started my diabetes journey with an A1C of 10.8. My best was 7.2, but now I'm back up to 7.4. I was EXTREMELY frustrated at my last appointment, which was about a week ago, but most of all disappointed in myself. I honestly thought I was doing better than that and to find out that I wasn't made me feel like all of my hard work wasn't worth it. I know 7.4 isn't bad, but it's not as good as I want it to be. 

I've been trying to "reprogram" my brain so that lows don't feel low. I'm not saying I ignore extreme lows, but unless I'm lower than 75, I'm not going to fix it. I have a CGM, so I know if I'm dropping. Also, for about the past month and a half, I have been doing manual boluses for after meal highs. I don't know how else to bring them down and I'm NOT ok with staying high until my next meal! I really think that my basal rates are really messed up.

I talked to my doctor's office today, and she told me to stop doing manual boluses after meals. I know that she needs to see how I react to meal boluses and basal rates, but I seriously feel that if I don't correct them manually, my A1C is going to get even higher. My goal for my next appointment (Feb.1st) is 7.0. I know that I have my whole life to master this disease, but I want to be in control of my health and by doing this, I feel like I'm letting go a little too much.

I feel like if I could only make minor changes in my basal rate every now and then, life would be so much better. After all, I'M the one living with this and only I know what I feel like every day!

What do you do, or what would you do?

Hi Erica!

Reading your post was like talking to a past version of myself.  A lot of what you said sounds familiar!

To answer your question, yes, I do adjust my basal rate on my own.  I have almost a quarter century of diabetes under my belt, and five years of pumping, so I feel comfortable doing that.  It sounds like you may need to bite the bullet and do some daytime basal testing - it's never fun, but that's the only real way you'll know what needs to be adjusted.

Has your doctor specifically told you not to change your rates on your own?

Best of luck,


I tweak my own.  I am much higher first thing in the morning than in the late afternoon.  How did you set your basal rates originally?

My doctor never gave me permission, but I also never specifically asked. How do you do basal testing?

I think usually you do it for 6-8 hours at a time.  Just don't eat, and test your blood sugar often.  If your basal rate is right, your blood sugar won't change by much either up or down.  That way you know the pump is giving you the same amount of insulin a function pancreas would.


So one day, say, you do it from morning to early afternoon.  And another day, you can test in the afternoon.  The key is to not have any residual food still being converted into sugar in the blood when you start.  Obviously you can't eat a big piece of cake and then start....


If you do the testing in various times of day, you can get a sense if your basal rates are set right over the course of all 24 hours in the day.

We don't change any settings in Chasey's pump without her doctor. They make all the changes when we see them. If we have a concern between appointments, we upload her info, call her endo and she will phone us back and make the changes over the phone with us. We test lots to give her lots of numbers to work with and if it's something urgent she is just a phone call away. Also our nutritionist at the diabetes clinic is also the pump trainer for medtronic so if the endo isn't available, she can also help us make adjustments with the settings. We also run two different programs on Chasey's pump and I just feel more secure with the endo making the changes.

My doctor just completely guessed on my basal rates when I started on the pump, which was almost 2 years ago. So if I were doing a self test, I would just fast for 6-8 hours at a time? So from like 7am to 1pm one day, 1pm - 7pm another day, and 7pm to 1am another day? Overnight would just be the same, right? How often do you check? Every hour?

Erica -

Brian explained it exactly right.  You also would want to avoid doing corrective boluses during this time (unless, of course, things get out of hand - then correct, and try again another day).

Sounds like you've got it.  Testing every hour is what's been recommended to me.  I sometimes test more often than that, but once an hour is the recommendation.

Or, since you've got a CGM, make sure you trust your current sensor and use that information, in addition to testing. 

I change my basals myself occasionally, but not often. I have a mac and can't download my pump or CGM, so I have a hard time seeing patterns. 

I tweak my basal rate by myself as I see fit.  Like Kim, I have been T1 a LONG time (33 years) and pumping for > 6 years so I feel very at home doing this.

I usually make basal pattern alterations based upon changes I can feel or predict with my body.  A great example is the changes I made just 3 weeks ago.  I reached the end of the race season, and planned on taking about 3 weeks away from hard training on the bike.  So, although I would still be riding and working out, I went from 15-20 hours a week in the saddle to 5-8 hours. 

I could have just fiddled with temp basals the whole time to adjust for the resulting lessoning of sensitivity, but I figured it would be easier to make the changes to the basal pattern itself.

I do use the PC program to backup and change my pump settings, so it was fairly simple.

Extra testing and CGM monitoring is indeed on order after any changes.  

To me self management is an necessary for successfully beating diabetes.  You just need to be confident in the knowledge that you have to do so.  If unsure, it is ALWAYS prudent to contact the Dr., Nurse, or CDE to discuss it before doing.  

Just my 2 cents.

Guilty as charged when it comes to tweaking the basal without telling docs. My A1C is off a bit from last 3 months (6.5 now, 6.3 then). You do need to at least tell your doctor, nurse or endo before you tweak your basal. My ANP was understanding but shook her head a lot when I told her.

Sarah's doctors have instructed me to go ahead and tweak as needed. Unless I see a big, glaring pattern of highs or lows, I usually download her pump about once a week and look for patterns. Most often I just do a little tweaking at a time, and give it a few days to see if there's improvement. For example, I began noticing this week that she's been high (180-200ish) each evening, so I adjusted her I:C ratio last night from 1:26 to 1:23. I'll check again in a few days, and see if I need to make further adjustments.

The doc gave me permission to change my basals if I feel I need to. In fact, he encourages it! My a1c appointment was today and it was 7.4 too! I agree it's not my best but its not my worst either.

Basically, I started changing my basals when I noticed my routinely checks were always high. Especially in the morning, my blood sugar would be up there. After breakfast (which usually consists of one granola bar), no matter how much insulin I took it always seemed to be up there. I experimented by keeping my routinely checks, not adding any more in between my regular checks unless I felt low, if the numbers remained high those days I upped that basal rate. I also ended up adding 2 nightly basals - one from 12 am to 2 am. and the other from 2 am to 6:30 am, both with different rates of insulin. That's definitely helped me a lot. However, the doc had me up my 6:30 basal yet again because he still felt my sugars were too high when I woke up.

In simpler terms, Diabetes is one big guessing game! o.O

Wishing all the luck! :)

I find it strange that people feel they need their endo's permission to change any setting on their pumps.  That pump is like a part of your body and just like any other body part, it's yours to maintain.  Now I'm not suggesting anyone make extreme changes or wild guesses.  If you feel you have a good understanding of basal, I:C ratios, ISF and IOB, AND you feel comfortable doing it, you shouldn't feel like you are sneaking behind your doctor's back.  I make changes all the time to my daughter's pump. A bit of a disclaimer though, I am a pediatric nurse so I might be a little more comfortable doing this than others.  I love the book Think Like a Pancreas by Gary Scheimer.  It gives detailed instructions on how to do basal testing.  If you decide to try changes yourself, good luck, just make small changes.  If you decide you want your MD's input, don't be ashamed of that.  Call him/her and let them help you. That's what they get paid for!

I think you have just proved that Diabetes is NOT just one big guessing game.  You analyzed your BG patterns and your needs, and made an adjustment.  That is an excellent use of power over Diabetes.  

Over my 33 years I have learned that this type of attention and "maintenance" corrections is always going to be required.   Your body is always in a state of flux, and, hence, your diabetes care will have to as well.

Just for fun (and I have this posted on here are the 2 basal patterns I currently use:

Riding Daily(Mon-Fri):
00:00 1.10u per/hr
01:00 1.15u per/hr
04:00 1.20u per/hr
06:00 1.20u per/hr
08:00 1.05u per/hr
15:00 1.00u per/hr
16:00 0.90u per/hr
22:00 1.00u per/hr

Ride Sat/Sun(Sat-Sun):
00:00 1.10u per/hr
01:00 1.15u per/hr
04:00 1.20u per/hr
06:00 1.15u per/hr
07:00 1.00u per/hr
10:00 0.90u per/hr
16:00 0.95u per/hr
18:00 1.15u per/hr

John Walsh's "Pumping Insulin" gives great info on testing basal rates.  I think it's good to test them a couple times a year.  I've pumped for about 8 years and my basals have always changed slightly.  

I do it by fasting for a day and testing every hour or 2.  Make sure you haven't had any bad highs or lows the day before or eaten a high carb or high fat meal within the last 6 hours before you start. 

I have a Mac too. I really wish they would make the Medtronic CareLink program compatible with Mac's!

Thank you everyone for your advice! I'm probably going to try fasting this weekend and see how it goes!