Basal Insulin Initiation

Do We Still Need Insulin?

Type 2 diabetes (T2D) is a progressive disorder characterized by multiple pathophysiological defects. The core defects include insulin resistance in the muscle and liver and impaired insulin secretion due to β-cell failure [1, 2]. The progressive nature of the disease is such that it requires therapy to be intensified over time to compensate for the ongoing β-cell deficiency [2,3,4]. At the time of T2D diagnosis, more than 50% of β-cells have already been lost, and continue to decline at an average rate of 5% per year [1, 2, 5]. Therefore, the use of insulin is an appropriate option at any point in the management of T2D to replace the insulin that the pancreas is unable to produce sufficiently [1, 6]. In fact, when the maximum output of insulin has decreased to 15% or 20% of normal, non-insulin anti-hyperglycemic agents can no longer sustain glycemic control and insulin supplementation becomes a necessity [5]. The usual starting point for insulin therapy in T2D is with basal insulin owing to its simplicity and lower risk of hypoglycemia [7].

When and in Whom to Initiate Insulin in T2D

The panel recommendations as to when and in whom to initiate insulin are summarized in Table 1.

Table 1 When and in whom to initiate insulin in T2D

What are the Barriers to Insulin Initiation?

Clinical inertia, defined as the failure on the part of the provider to advance therapy when required, adversely affects timely management of T2D [9,10,11,12]. Insulin is often initiated late in the course of the disease, after failure with multiple antihyperglycemic agents, and at glycemic values well above the recommended targets [11,12,13,14,15]. In Canada, mean A1C levels are > 8.5% and mean diabetes duration is ≥ 9 years before initiation of basal insulin in T2D patients [13, 15]. A UK retrospective study of pharmacologically treated T2D patients on one, two, or three oral antihyperglycemic agents reported that the median time to insulin initiation was > 7 years with an A1C ≥ 7.0% and the mean A1C levels at initiation was > 9.0% [12].

There are many barriers that contribute to this delay in initiation and intensification of insulin in T2D. It is important to emphasize that many of these barriers reflect the attitudes and beliefs of both patient and provider. Identifying and addressing both provider and patient beliefs and attitudes are therefore essential to mitigate those barriers (Tables 2 and 3).

Table 2 Provider barriers
Table 3 Patient barriers [39,40,41,42,43]

What is Your Role in Insulin Therapy?

Success in overcoming patient barriers relies greatly on listening to the patient and proactively addressing their fears and concerns [55, 56]. Open dialogue with the patient throughout the continuum of diabetes management, with an emphasis on the positive benefits of insulin therapy, will significantly enhance the outcomes for patients with diabetes. See Table 4 for review of action points with your patient.

Table 4 A new LEASE on insulin management [55]

Basal Insulin Dose and Titration Recommendations

In light of the persistent barriers contributing to delays in diabetes management with insulin, there is an urgent need for a simplified and practical approach to the initiation and intensification of insulin. Complex regimens and unrealistic targets can worsen the patient’s engagement in the process and ultimately the patient’s well-being [3, 4, 57]. Simplification allows for empowerment by engaging the patient in doable tasks, which provides the context for behavior shaping (next step goals) and self-efficacy (confidence in the face of barriers) [58].

What Do We Want in a Basal Insulin Recommendation?

  • A starting dose that can be safely applied and individualized.

  • A titration schedule that is simple and can be safely patient-driven, with a fasting blood glucose (FBG) target that can be individualized. Patient-driven titration schedules are as effective as provider-driven titration schedules [19, 59,60,61,62,63,64] and engage the patient, which in turn can lower barriers to insulin therapy [4, 65, 66].

  • Clear instructions to the patient on how the dose will be titrated, to manage expectations which will empower the patient and improve adherence to therapy [3, 4, 16, 66].

  • Recognition that insulin initiation and titration are two separate behaviors for the patient, each of which needs to be addressed in relation to patient readiness to change.

How to Select a Basal Insulin?

Three generations of basal insulins are available in Canada. The first generation of basal insulin is NPH, a human insulin that has been available for many decades, since 1946. The basal analogues (insulins detemir and glargine (Gla-100)) emerged in the 2000s and provided longer duration of action, improved day-to-day variability, reduced hypoglycemia, especially nocturnal, and did not require resuspension (as does NPH) [67]. A next generation of long-acting basal insulins—insulins glargine 300 U/mL (Gla-300) and degludec—have emerged with an extended action profile, improved safety, and the advantage of being administered in smaller volumes [29]. Table 5 summarizes the main characteristics of the currently available basal insulins. The panel recognizes that the choice of basal insulin may depend on access, cost, and clinical judgment with respect to the patient’s individual needs and lifestyle [29].

Table 5 Basal insulins

How to Dose?

There are several important concepts to remember when dosing basal insulin: (a) the starting dose will be wrong; (b) there is no maximal insulin dose; (c) titration of insulin dose is the key [8]. Each of these concepts needs to be explicitly discussed and understood by the patient in order for titration to be successful. Despite 92% of physicians agreeing that “insulin intensification is an essential element of diabetes management,” 30% of primary care physicians “never or rarely” personally intensified insulin (vs 4% of specialists) in the multinational survey MODIFY [14, 81]. Interestingly, in a recent multinational survey, HCPs generally preferred a gradual and safe approach to titration to avoid hypoglycemia whereas patients are frustrated by time to reach goal [66]. It is therefore important to manage the patient’s expectations.

The starting dose for basal insulin recommended by this panel is 10 U/day. The dose should be incrementally increased on a regular basis using target FBG as the determinant for dose adjustments. At initiation, educating patients that many people will need at least 40–50 units of basal insulin to achieve target FBG is useful for goal setting and behavior shaping. This may help mitigate patient fear/reluctance to up-titrate [8].

Box 1A details the recommendations by the panel for basal insulin dose and titration.

Box 1B provides a summary of key recommendations, including a starting dose and titration schedule.

Basal Insulin Dose and Titration Recommendations (2017)

Box 1A: 2017 recommendations by the panel for basal insulin dose and titration


Panel recommendations


The initial dosea

10 U/day

[19, 22, 59]

Other considerations:

  0.2 U/kg/day [68, 82]

  Using FBG as starting point: e.g., if FBG is 16 mmol/L start at 16 U [59]

May need to be lower for some patients—recall that the starting dose should be individualized [14]

The lower dosages have the advantage of decreasing the risk of a hypoglycemic reaction with the first injection, but make the titration period a bit longer

Discuss and negotiate your patient’s expectation

Fasting SMBG target

Target should be 4.0–7.0 mmol/L for most people

  Patient/HCP contact recommended at 7.0 mmol/L. HCP may then suggest continuing to 4.0–5.5 mmol/L

[19, 20, 59, 80, 83,84,85]

Individualize target with a step approach (within 3 months) [14]

Important to educate that diabetes is a progressive disease and this is a moving target [4]

Dose adjustments

Select a simple titration algorithm that matches patient lifestyle [57]

The following dose adjustment algorithms have been shown to be safe and effective. Select the one that is easiest for the patient to follow:

One easy titration algorithm is

1 unit every dayb [19, 63, 64, 66]

Other titration algorithms include:

2 units twice weekly based on lowest fasting SMGB value of the last 3 days [26, 27, 62, 86]

Every week, based on lowest fasting SMGB value of the last 3 days [26, 63, 64]

Other considerations:

  If (nocturnal) hypoglycemia occurs (BG < 4.0 mmol/L) reduce the dose by 2–4 units, or 10% of the basal dose based on clinical judgement [57]

  For other considerations, see Table 6

Measure glucose level at least every morning before breakfastc [57]

Remind patient to adjust the basal insulin based on morning glucose not bedtime glucosec [57]

Assess for possible hypoglycemia (< 4.0 mmol/L) and decrease titration [52]

Recognize that patient fear of hypoglycemia is easily elicited (hypoglycemia is a traumatic stress) and that providers underestimate the psychological impact of nonsevere hypoglycemia [51]

Mitigating hypoglycemia:

Is there an identifiable cause? [52]

Teach patients how to prevent, recognize, and treat hypoglycemia [52]

Confirm with patient that it is not “pseudo-hypoglycemia”. Explain what pseudo-hypoglycemiad is and ways to mitigate it [54]

If no identifiable and preventable cause is identified, reduce the dose

Confirm patient is using an accurate glucometer

Optimal/maximum basal insulin dose

Educate the patient of their expected dose [3, 57]

In most studies: 40 to 50 units is needed [8, 19, 26, 27, 66]

Communicate how long it will take them to reach target (e.g., if the expected dose is 60 units at 1 U/day increase, then it will take on average 6 weeks)

Indication that basal insulin is not enough includes:

Up-titrations without a corresponding drop on BG (verify patient adherence and check injection sites).

Patient has surpassed 1 U/kg/day of basal insulin without sufficient FBG control [87]

FBG in target, but A1C above target

  1. BG blood glucose, FBG fasting blood glucose, SMBG self-monitored blood glucose
  2. aFor more information on how to handle any oral agents and other FAQs, see Tables 6 and 7
  3. bAlgorithm proven safe and effective with insulin glargine 100 units/mL (Lantus®) and 300 units/mL (Toujeo™)
  4. cAdjust accordingly if shift worker
  5. dPseudo-hypoglycemia: an event in which the patient experiences symptoms of hypoglycemia with a BG > 3.9 mmol/L but approaching that level [54]
    figure a

Frequent Questions and What to Do with Previous Drugs When Initiating Basal Insulin

Tables 6 and 7 outline some of the frequently encountered questions and concerns facing HCPs when initiating and titrating basal insulin.

Table 6 Frequently asked questions and concerns
Table 7 What to do with previous drugs [8, 57, 91, 92]: usually continue all current anti-hyperglycemic agents when initiating basal insulin

Patient Support and Medical Follow-up

How to Ensure Success of Basal Insulin Management?

The success of basal insulin initiation and titration relies not only on identifying and addressing the patient and practitioner barriers but also on contact frequency with the patient. Post-initiation follow-up may occur by many means including via phone, text, email (depending on jurisdiction), cloud, or virtual consult. Regular contact presents an opportunity to provide or revisit diabetes education, to provide support to patients on how to effectively self-manage their disease and to identify any causes of concern [3, 34]. Furthermore, titration should be revisited when the patient is not achieving goal, hypoglycemia occurs, or there is a change in the insulin type or brand (e.g., biosimilar) [87].

The panel provides guidelines for medical follow-up with patients in Box 2.

Panel Recommendations for Medical Follow-up with Diabetes HCPs

Box 2: panel recommendations for medical follow-up with diabetes HCPs [87, 91]


What and why

24–72 h

When initiating insulin or titration

Support insulin initiation and reinforce titration

1–2 week(s)

Patients report BG readings

Ensure titration is occurring normally

1 month

Patients report BG readings

Ensure titration is occurring normally (it is encouraged to continue with biweekly contacts thereafter)

3 months

A1C measurement

If not at goal, patient may continue with titration for another 3 months

This contact point should occur in person or by virtual consult

6 months

A1C measurement

Follow-up of titration

If A1C above target, review glycemic profile and consider adding mealtime insulin

Within 24 h of hypoglycemia

Educate patient on recognizing, preventing, and treating hypoglycemia

If recurrent hypoglycemia occurs, re-evaluate titration schedule or reduce dose (frequent, recurrent hypoglycemia is typically defined as 1–2 lows in 1 week)


Several factors underlie the importance of the initiative put forth by this expert panel: there is a rising prevalence of diabetes [98]; half of the T2D population is not at target, among which 61% were receiving insulin therapy [99], suggesting delayed insulin initiation and intensification; there are multiple titration algorithms to choose from which adds to the confusion and complexity for patients and providers; and the arrival of new long-acting basal insulins and other pharmacological and technological advances that require consideration. This document was developed by a multidisciplinary panel to address frequently asked questions on insulin initiation and titration, and it establishes simple and practical guidelines for diabetes HCPs for effective initiation and titration of basal insulin, with the intent that it may translate to effective glycemic outcomes in clinical practice.

Compliance with Ethical Guidelines

This article is based on previously conducted studies and does not contain any studies with human participants or animals performed by any of the authors.