- Article
- Source: Campus Sanofi
- 19 Nov 2025
How to start and switch insulin: a HCP guide
Starting patients on toujeo (insulin glargine U/300mL)¹
Toujeo is a basal insulin for once daily administration at any time of the day, preferably at the same time every day. When needed, patients can administer Toujeo up to 3 hours before or after their usual time of administration. The dose regimen (dose and timing) should be adjusted according to individual response.1 Toujeo is indicated for the treatment of diabetes mellitus in adults, adolescents and children from the age of 6 years.1
Toujeo is to be used once daily with meal time insulin and requires individual dose adjustments. Toujeo must be combined with short-/rapid acting insulin to cover mealtime insulin requirements.
The recommended daily starting dose is 0.2 units/kg followed by individual dose adjustments. Toujeo can also be given together with other anti hyperglycaemic medicinal products.
Toujeo is to be used once daily with meal time insulin and requires individual dose adjustments. Toujeo must be combined with short-/rapid acting insulin to cover mealtime insulin requirements.
The recommended daily starting dose is 0.2 units/kg followed by individual dose adjustments. Toujeo can also be given together with other anti hyperglycaemic medicinal products.
Switching from different basal insulins to toujeo1
Close metabolic monitoring is recommended during the switch and in the initial weeks thereafter, with potential dose adjustments and adjustments required to the patients’ treatment regime.
From insulin glargine U1001
- Insulin (glargine 100 units/mL) and Toujeo are not bioequivalent and are not directly interchangeable
- Initial switch: unit-to-unit basis
- Dose adjustment: May require a 10-18% higher dose
Example: Lantus (insulin glargine 100 units/mL) 40 units once daily = 40 units Toujeo (may need up to 47 units)
From once-daily insulins1
- On a unit to unit based on the previous basal insulin dose
From twice-daily insulins1
- 80% of total daily dose as Toujeo
- Example: 20 units morning + 15 units evening determir = 28 units Toujeo (80% of 35)
Practical Implementation2
- Check the DHSC Medicines Supply Notification and availability via the SPS Medicines Supply Tool.
- People with allergies to alternative insulins should be referred to local allergy or diabetes services as required.
- Evaluate co-morbidities, and prioritise those in high-risk groups, such as those below:
- Impaired hypoglycaemia awareness
- High glucose variability on CGM, history of severe hypoglycaemia or recurrent diabetic ketoacidosis (DKA)
- Evidence of lipohypertrophy at injection sites
- Frailty and/or older age
- Children and adolescents
- Renal or severe hepatic impairment
- Cognitive or functional impairment
- Learning difficulties or low health literacy
- Visual impairment and manual dexterity problems
- High alcohol intake or binge drinking
- High level of physical activity
- As part of the clinical review, assess whether the current insulin regimen in type 2 diabetes could be optimised by introducing / switching to different insulin types (e.g., rapid-acting, or mixed insulin) or by incorporating non-insulin therapies.
- When switching between insulins, there can be differences between absorption, potency, and action profile, therefore consider reducing doses by 10-20% to avoid the initial risk of hypoglycaemia.
- If lipohypertrophy is detected, considerable dose adjustment is often required when changing injection sites, seek advice and guidance as necessary if unsure.
- When prescribing new insulins, ensure any change in device type is explained to the patient with written product information provided. Patient resources and demonstration devices can be requested via sanoficares@sanofi.com or printed from mysanofiinsulin.co.uk
- For those with very erratic glucose levels, or disproportionately high insulin doses, assess injection technique and check for evidence of lipohypertrophy at injection sites.
- Education and support should be provided to help individuals self-adjust doses post-switch, where appropriate, along with a check of understanding of sick day rules.
- Ensure adequate safety netting, advising patients to report any concerns about glucose levels after following provided dose adjustment guidance.
- Risk of glucose instability is elevated during insulin changes. A clinical review with CBG/CGM data is helpful.
- Monitoring should rely on capillary blood glucose (CBG) at least four times daily, CGM, and ketone monitoring (where appropriate)—not HbA1c alone.
- People living with diabetes should be reviewed at 2-3 weeks to support with dose titration, as necessary. For those at higher risk of dysglycaemia aim for close clinical review within 1-2 weeks of change where possible.
- If there is uncertainty seek advice and guidance or refer to community / specialist diabetes services as per locally agreed pathways.
- Check the DHSC Medicines Supply Notification and availability via the SPS Medicines Supply Tool.
- People with allergies to alternative insulins should be referred to local allergy or diabetes services as required.
- Evaluate co-morbidities, and prioritise those in high-risk groups, such as those below:
- Impaired hypoglycaemia awareness
- High glucose variability on CGM, history of severe hypoglycaemia or recurrent diabetic ketoacidosis (DKA)
- Evidence of lipohypertrophy at injection sites
- Frailty and/or older age
- Children and adolescents
- Renal or severe hepatic impairment
- Cognitive or functional impairment
- Learning difficulties or low health literacy
- Visual impairment and manual dexterity problems
- High alcohol intake or binge drinking
- High level of physical activity
- As part of the clinical review, assess whether the current insulin regimen in type 2 diabetes could be optimised by introducing / switching to different insulin types (e.g., rapid-acting, or mixed insulin) or by incorporating non-insulin therapies.
- When switching between insulins, there can be differences between absorption, potency, and action profile, therefore consider reducing doses by 10-20% to avoid the initial risk of hypoglycaemia.
- If lipohypertrophy is detected, considerable dose adjustment is often required when changing injection sites, seek advice and guidance as necessary if unsure.
- When prescribing new insulins, ensure any change in device type is explained to the patient with written product information provided. Patient resources and demonstration devices can be requested via sanoficares@sanofi.com or printed from mysanofiinsulin.co.uk
- For those with very erratic glucose levels, or disproportionately high insulin doses, assess injection technique and check for evidence of lipohypertrophy at injection sites.
- Education and support should be provided to help individuals self-adjust doses post-switch, where appropriate, along with a check of understanding of sick day rules.
- Ensure adequate safety netting, advising patients to report any concerns about glucose levels after following provided dose adjustment guidance.
- Risk of glucose instability is elevated during insulin changes. A clinical review with CBG/CGM data is helpful.
- Monitoring should rely on capillary blood glucose (CBG) at least four times daily, CGM, and ketone monitoring (where appropriate)—not HbA1c alone.
- People living with diabetes should be reviewed at 2-3 weeks to support with dose titration, as necessary. For those at higher risk of dysglycaemia aim for close clinical review within 1-2 weeks of change where possible.
- If there is uncertainty seek advice and guidance or refer to community / specialist diabetes services as per locally agreed pathways.
References
-
Sanofi. Toujeo 300 units/mL solution for injection in a pre-filled pen - Summary of Product Characteristics (SmPC) 2024.
-
Association of British Clinical Diabetologists, Primary Care Diabetes Society. Levemir (insulin detemir) discontinuation: Guidance on switching to alternative basal insulins 2025.
MAT-XU-2504556(v1.0) | Date of Preparation: December 2025