Can Trulicity be used with Lantus? Yes, Trulicity (dulaglutide) and Lantus (insulin glargine) can be safely combined for managing type 2 diabetes mellitus. Trulicity is a glucagon-like peptide-1 (GLP-1) receptor agonist given once weekly, whilst Lantus is a long-acting basal insulin typically administered once daily. Their complementary mechanisms—Trulicity enhancing glucose-dependent insulin secretion and slowing gastric emptying, Lantus providing steady background insulin coverage—make them suitable for concurrent use. NICE guideline NG28 supports this combination as an intensification strategy, particularly for patients whose blood glucose remains inadequately controlled on basal insulin alone. This combination must be carefully managed by healthcare professionals to optimise dosing and minimise hypoglycaemia risk.

Can Trulicity Be Used With Lantus?

Yes, Trulicity (dulaglutide) can be used in combination with Lantus (insulin glargine), and this combination is both clinically recognised and supported by evidence-based guidelines. Trulicity is a glucagon-like peptide-1 (GLP-1) receptor agonist administered once weekly, whilst Lantus is a long-acting basal insulin typically given once daily. Both medications are used to manage type 2 diabetes mellitus, and their complementary mechanisms of action make them suitable for concurrent use in patients who require additional glycaemic control.

The combination is particularly relevant for individuals whose blood glucose levels remain inadequately controlled on basal insulin alone, or conversely, for those on GLP-1 therapy who require the addition of basal insulin. NICE guideline NG28 acknowledges the use of GLP-1 receptor agonists alongside basal insulin as an intensification strategy for type 2 diabetes management, typically with specialist involvement. Both medications hold UK marketing authorisations, and their respective Summaries of Product Characteristics (SmPCs) confirm that dulaglutide can be used as an add-on therapy to insulin.

When used together, Trulicity and Lantus target different aspects of glucose regulation: Trulicity enhances glucose-dependent insulin secretion, suppresses glucagon release, and slows gastric emptying, whilst Lantus provides steady background insulin coverage to control fasting glucose levels. This dual approach can lead to improved HbA1c reduction compared to either agent alone. However, the combination must be carefully managed by healthcare professionals to optimise dosing, minimise the risk of hypoglycaemia, and monitor for potential adverse effects. Patients should never initiate or adjust this combination without medical supervision.

Clinical Evidence for Combining Trulicity and Lantus

Robust clinical trial data support the efficacy and safety of combining GLP-1 receptor agonists like Trulicity with basal insulins such as Lantus. The AWARD programme (Assessment of Weekly AdministRation of LY2189265 in Diabetes) includes several studies demonstrating the benefits of dulaglutide when added to insulin therapy. Specifically, the AWARD-9 trial evaluated dulaglutide in combination with insulin glargine and showed significant HbA1c reductions (approximately 1.4% with dulaglutide 1.5mg vs 0.7% with placebo) alongside weight benefits, which is particularly advantageous given that insulin therapy alone often leads to weight gain.

Further evidence from real-world studies and meta-analyses confirms that adding a GLP-1 receptor agonist to basal insulin therapy improves glycaemic control whilst potentially reducing insulin requirements. Patients typically experience HbA1c reductions of 0.5–1.5% when Trulicity is added to existing basal insulin regimens. Importantly, this combination has been associated with weight loss or weight neutrality, contrasting with the weight gain commonly seen with insulin intensification alone.

The European Medicines Agency (EMA) and NICE recognise this combination as an evidence-based treatment option for adults with type 2 diabetes who have not achieved target glucose levels with basal insulin, metformin, and other oral agents. NICE guidance (NG28) specifically recommends considering a GLP-1 receptor agonist in combination with insulin therapy for patients with a BMI of 35 kg/m² or higher (or lower thresholds for people from certain ethnic backgrounds), or when insulin therapy has resulted in significant weight gain or problematic hypoglycaemia. This combination therapy should be initiated and monitored by a specialist care team.

Clinical studies have also demonstrated that the combination is generally well tolerated, with the most common adverse effects being gastrointestinal symptoms from Trulicity and hypoglycaemia risk from insulin, both of which can be managed through appropriate dose titration and patient education.

Dosing and Administration Considerations

When initiating the combination of Trulicity and Lantus, careful attention to dosing and administration timing is essential to optimise efficacy and minimise adverse effects. Trulicity is administered subcutaneously once weekly using a pre-filled pen, and can be given at any time of day, with or without meals. The typical starting dose is 0.75 mg weekly, which may be increased to 1.5 mg weekly after at least 4 weeks if additional glycaemic control is needed. Higher doses (3 mg and 4.5 mg) are available but should only be considered after at least 4 weeks at each previous dose level, as specified in the Trulicity SmPC.

Lantus is administered subcutaneously once daily, preferably at the same time each day to maintain consistent basal insulin coverage. When adding Trulicity to an existing Lantus regimen, the Trulicity SmPC advises that healthcare professionals should consider reducing the insulin dose to mitigate hypoglycaemia risk. Local protocols may recommend reductions of 10–20%, particularly during the initial weeks as Trulicity's glucose-lowering effects become established. Conversely, when adding Lantus to existing Trulicity therapy, insulin is typically started at a conservative dose according to local protocols and NICE guidance, and titrated gradually based on fasting glucose readings.

Both medications are injected subcutaneously and patients should rotate injection sites to prevent lipodystrophy. Common injection sites include the abdomen, thigh, or upper arm. The medications should never be mixed in the same syringe.

Dose adjustments should be guided by self-monitoring of blood glucose (SMBG) and regular HbA1c measurements. Patients typically monitor fasting glucose levels to guide Lantus titration, whilst overall glycaemic control and postprandial glucose may inform Trulicity dose adjustments. Healthcare professionals should provide clear written instructions regarding dose titration schedules, target glucose ranges, and when to seek advice. Regular review appointments are essential, particularly during the first three months of combination therapy.

Potential Side Effects and Safety Monitoring

The combination of Trulicity and Lantus carries specific safety considerations that require vigilant monitoring. The most significant concern is hypoglycaemia (low blood glucose), which can occur when insulin and GLP-1 receptor agonists are used together. The risk of hypoglycaemia may be mitigated by appropriate insulin dose adjustment when starting dulaglutide. Patients should be educated to recognise hypoglycaemia symptoms—including tremor, sweating, confusion, palpitations, and hunger—and know how to treat episodes promptly with fast-acting carbohydrates.

Gastrointestinal side effects are common with Trulicity, particularly during initial treatment. These include nausea (occurring in approximately 10–20% of patients), vomiting, diarrhoea, abdominal pain, and decreased appetite. These symptoms typically diminish over several weeks as tolerance develops. Patients should be advised to eat smaller, more frequent meals and avoid high-fat foods during the adjustment period. Severe or persistent vomiting or diarrhoea warrants medical review due to dehydration risk.

Injection site reactions may occur with either medication, manifesting as redness, itching, or swelling at the injection site. These are usually mild and self-limiting. More serious but rare adverse effects include pancreatitis (acute inflammation of the pancreas), which has been reported with GLP-1 receptor agonists. Patients should be instructed to seek immediate medical attention if they experience severe, persistent abdominal pain, particularly if radiating to the back and accompanied by vomiting. If pancreatitis is suspected, dulaglutide should be discontinued immediately.

Regular monitoring should include:

• HbA1c measurements every 3–6 months

• Renal function tests (eGFR and urine albumin-creatinine ratio) annually or more frequently if impaired

• Body weight and BMI at each review

• Blood pressure monitoring

• Lipid profile annually

• Assessment for diabetic complications (retinopathy, neuropathy, foot health)

The Trulicity SmPC notes that in rodent studies, GLP-1 receptor agonists have been associated with thyroid C-cell changes, but the human relevance of this finding is unknown. Patients should report any suspected side effects to their healthcare professional or directly to the MHRA Yellow Card Scheme.

When to Speak With Your Healthcare Team

Patients using the combination of Trulicity and Lantus should maintain regular contact with their diabetes healthcare team and know when to seek urgent advice. Routine follow-up appointments are typically scheduled every 3–6 months to review glycaemic control, adjust medications, and screen for complications. However, certain situations require more immediate consultation.

Contact your GP or diabetes nurse promptly if you experience:

• Recurrent hypoglycaemia (more than one episode per week) or severe hypoglycaemia requiring assistance

• Persistent nausea, vomiting, or diarrhoea lasting more than 48 hours

• Unexplained weight loss exceeding 5% of body weight

• Symptoms of hyperglycaemia (excessive thirst, frequent urination, fatigue) despite medication adherence

• Signs of infection, particularly urinary or respiratory infections, which may affect glucose control

• Difficulty managing your medication regimen or confusion about dosing

Seek immediate medical attention (call 999 or attend A&E) if you develop:

• Severe, persistent abdominal pain, especially if radiating to the back (possible pancreatitis)

• Signs of diabetic ketoacidosis (DKA): excessive thirst, frequent urination, nausea, vomiting, abdominal pain, fruity breath odour, confusion

• Severe hypoglycaemia with loss of consciousness or seizures

• Allergic reactions such as difficulty breathing, facial swelling, or widespread rash

For urgent but non-emergency concerns outside of normal hours, contact NHS 111 for advice.

Before any planned surgery or medical procedures, inform your healthcare team about your diabetes medications, as temporary adjustments may be necessary. Perioperative management should follow local surgical/anaesthetic guidance for GLP-1 receptor agonists. Similarly, if you develop acute illness, particularly with vomiting or reduced oral intake, contact your diabetes team for sick day guidance, as both Trulicity and Lantus doses may require modification.

Pregnancy planning is crucial: Trulicity should be stopped at least 1 month before planned conception and is not recommended during pregnancy. Insulin requirements change significantly during pregnancy and require specialist management. Women of childbearing potential should discuss contraception and diabetes management with their healthcare team. Regular engagement with your diabetes care team ensures optimal outcomes and helps prevent both acute and long-term complications.

Frequently Asked Questions