Your Total Daily Dose (TDD) of insulin is your most crucial rudder in diabetes management. A low TDD elevates glucose, while a high TDD causes frequent lows. An optimal TDD is your best guide to better average glucose and pump settings that work! Everything depends on an accurate TDD, which is essential for success on an AID device. If you have frequent lows or mostly highs, focus first on adjusting your TDD.
Smart Insulin Pens
On multiple daily injections (MDI), a smart insulin pen like the Companion Diabetes InPen or the Novo Nordisk EchoPen is extremely handy. These pens keep track of meals and correct doses using a smartphone app. Both have great bolus calculators that track and appropriately subtract IOB. A smart pen makes it a lot easier for you and your clinician to keep a record of the rapid insulin you take. Adding a 14-day average of your short-acting insulin to the units of long-acting insulin you take daily will give you an accurate TDD to determine basal/bolus balance and more precise insulin doses and bolus calculator settings.
Total Daily Dose is an average of your daily basal insulin units plus bolus insulin units over at least 14 days of pump wear. Your pump averages your TDD for you. If you use MDI, add up all the long-acting and short-acting insulin doses you take daily for 1 or 2 weeks and divide the total by 7 or 14.
Find your average TDD on injections with Workspace 9.1 from Pumping Insulin.
9.1 Find your Average TDD on Injections
- Record all your daily doses of long-acting* and rapid-acting* insulin for a week or more on paper or a phone app.
- After seven or more days, add all the daily doses of long-acting* and rapid-acting* insulin.
- Divide this total by the number of days you’ve been recording them. (For example, 210 total units in 7 days = 210 ÷ 7 = 30 u/day as your current average TDD.)
My average TDD = _____units per day
* Long-acting includes every long-acting insulin dose you take each day. Rapid-acting insulin includes your meal and snack doses PLUS all correction doses taken for high readings during these days.
Evaluate Your TDD
High TDDs Cause Frequent Lows
Stop frequent lows first. An excessive TDD is easily identified by the frequent hypoglycemia it generates, usually four or more glucose readings below 60 mg/dL each week that occur at different times of the day. Here, the degree of excess in the TDD cannot be accurately measured. Start with a 5% or 10% reduction in your current TDD by multiplying it by 0.95 or 0.90, respectively. Enter this reduced TDD into the Pump Settings Tool to adjust your basal rates, CarbF, and CorrF. If needed, lower your TDD until the lows gradually disappear.
As you lower your TDD, you usually reduce the larger of your basal or bolus units first, or if they’re about equal, lower both(i.e., lower basal rates and higher CarbF and CorrF numbers). Once the lows are not generating highs and your glucose is more stable, it becomes much easier to find accurate pump settings.
Glucose Patterns may be the Problem when your Average Glucose and A1c are OK
Spotting and correcting these patterns are best done with Pattern Management[link to Use-Pattern-Management], especially when your average glucose is relatively good but unwanted patterns persist. With an average glucose between 125 and 183 mg/dL, your TDD is reasonably close to ideal. Here, Pattern Management helps eliminate unwanted patterns.
Low TDDs Cause Highs
Many pump wearers are dealing with a different issue: elevated glucose readings, such as those that average above 183 mg/dL or an A1c of 8% or higher with few lows. The Pump Settings Tool offers a convenient way to find a conservative increase in your TDD. An optimized TDD can be found in the right column, and below that are optimized settings for your average Basal Rate, CarbF, and CorrF. Write the numbers in the right column down or print this page. The increase in your TDD in the column on the right requires a recent, accurate 14-day average glucose from your CGM or a recent A1c test result.
9.2 Find An Expected TDD for Your Weight
- Enter your current weight and multiply by 0.24 for lbs (or 0.53 for kg) to find the expected TDD for your weight with normal insulin sensitivity.*
My weight x 0.24 (for lbs) or 0.53 (for kg) - Expected TDD = _____ units/day
*For children before puberty, multiply by 0.20 for lbs or 0.44 for kgs.
Your Weight Defines Your Expected TDD
If you’re new to pumping, you and your doctor can find an expected TDD based on a person of your weight who has an average sensitivity to insulin.
It’s time to get hands-on! These improved pump settings will now be tested. In our testing section, we’ll cover how to check your Basal Rate, carbF/ISF, and corrF/ISF for accuracy.
Let’s start with your most important setting, Basal Rate(s).