Trulicity: Uses, Dosage & Side Effects

What Is Trulicity and What Is It Used For?

Trulicity contains the active substance dulaglutide, a long-acting glucagon-like peptide-1 (GLP-1) receptor agonist designed specifically for once-weekly administration. The molecule consists of two copies of a modified GLP-1 analogue covalently linked to a modified human immunoglobulin G4 (IgG4) Fc fragment. This innovative molecular design serves two critical purposes: it protects the GLP-1 component from rapid enzymatic degradation by dipeptidyl peptidase-4 (DPP-4), and the large IgG4 Fc fragment slows renal clearance, resulting in a plasma half-life of approximately 5 days that supports convenient once-weekly dosing.

GLP-1 is one of the key incretin hormones naturally produced in the gut in response to food intake. In healthy individuals, GLP-1 plays several crucial roles in glucose homeostasis: it stimulates glucose-dependent insulin secretion from pancreatic beta cells (meaning it primarily works when blood sugar is elevated), suppresses inappropriate glucagon secretion from pancreatic alpha cells, slows the rate of gastric emptying (which moderates post-meal glucose spikes), and promotes satiety through central nervous system mechanisms. In patients with type 2 diabetes, the incretin effect is significantly impaired, contributing to the characteristic hyperglycemia of the condition.

Dulaglutide restores and enhances the action of GLP-1 by binding to and activating the GLP-1 receptor with high potency. Because its insulin-stimulating effect is glucose-dependent, dulaglutide carries a substantially lower risk of causing hypoglycemia compared with sulfonylureas or insulin when used as monotherapy or in combination with metformin. This glucose-dependent mechanism is a fundamental safety advantage of the GLP-1 receptor agonist class.

Trulicity is indicated for the treatment of adults and children aged 10 years and older with type 2 diabetes mellitus in the following clinical scenarios:

• Monotherapy: When diet and exercise alone do not provide adequate glycemic control and metformin is not suitable due to intolerance or contraindications.
• Combination therapy: In combination with other glucose-lowering medications, including metformin, sulfonylureas, thiazolidinediones, SGLT2 inhibitors, and/or basal insulin, when these agents together with diet and exercise do not provide adequate glycemic control.
• Cardiovascular risk reduction: To reduce the risk of major adverse cardiovascular events (MACE) in adults with type 2 diabetes who have established cardiovascular disease or multiple cardiovascular risk factors.

The efficacy of Trulicity has been extensively evaluated in the AWARD (Assessment of Weekly AdministRation of LY2189265 in Diabetes) clinical trial program, one of the largest phase III programs ever conducted for a diabetes medication. The AWARD program comprised multiple randomized, controlled trials involving over 6,000 patients, comparing dulaglutide against placebo, active comparators (including metformin, sitagliptin, exenatide twice daily, and insulin glargine), and evaluating its use across a wide range of treatment settings.

Key findings from the AWARD trials demonstrated that Trulicity at the 1.5 mg dose typically reduced HbA1c (a measure of average blood sugar over 2–3 months) by approximately 1.0–1.6 percentage points from baseline, with a substantial proportion of patients achieving the treatment target of HbA1c below 7%. In the AWARD-3 trial, dulaglutide 1.5 mg demonstrated superior HbA1c reduction compared with metformin at 26 weeks. In AWARD-6, it showed non-inferiority to liraglutide 1.8 mg daily. The higher doses of 3 mg and 4.5 mg, approved more recently, provide additional glycemic lowering for patients who need more intensive treatment.

The cardiovascular benefits of Trulicity were established in the landmark REWIND (Researching Cardiovascular Events with a Weekly Incretin in Diabetes) trial, a large-scale, randomized, placebo-controlled trial involving 9,901 patients with type 2 diabetes across 24 countries, followed for a median of 5.4 years. REWIND was unique among cardiovascular outcomes trials for GLP-1 receptor agonists because it included a broad population, with the majority of participants (69%) not having prior cardiovascular events at baseline. The trial demonstrated a statistically significant 12% reduction in the primary composite endpoint of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke (hazard ratio 0.88, 95% CI 0.79–0.99, p=0.026).

Trulicity was first approved by the U.S. Food and Drug Administration (FDA) in September 2014 and by the European Medicines Agency (EMA) in November 2014. It is now approved in more than 60 countries worldwide and has become one of the most widely prescribed GLP-1 receptor agonists globally, with over 10 million patients treated since its launch.

What Should You Know Before Taking Trulicity?

Contraindications

Trulicity must not be used if you have a known allergy (hypersensitivity) to dulaglutide or any of the other ingredients in the formulation. The excipients include sodium citrate, citric acid, mannitol, polysorbat 80, and water for injections. If you have experienced a severe allergic reaction to any GLP-1 receptor agonist, discuss this with your doctor before starting Trulicity.

In the United States, Trulicity carries a boxed warning regarding the risk of thyroid C-cell tumors. In animal studies, dulaglutide and other GLP-1 receptor agonists caused dose-dependent thyroid C-cell tumors (including medullary thyroid carcinoma) in rodents. While it is unknown whether Trulicity causes thyroid C-cell tumors in humans, Trulicity is contraindicated in patients with a personal or family history of medullary thyroid carcinoma (MTC) or in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). Patients should be counseled about the potential risk and advised to report symptoms such as a lump or swelling in the neck, hoarseness, difficulty swallowing, or persistent shortness of breath.

Warnings and Precautions

Before starting Trulicity, discuss the following with your healthcare provider:

• Pancreatitis: If you have had pancreatitis (inflammation of the pancreas) in the past, Trulicity may not be appropriate. Symptoms of pancreatitis include severe abdominal pain that may radiate to the back and does not subside. Seek immediate medical attention if you experience these symptoms.
• Severe gastrointestinal disease: Trulicity slows gastric emptying and is not recommended for patients with severe gastroparesis (delayed stomach emptying) or other severe gastrointestinal conditions. Symptoms such as persistent nausea, vomiting, or feeling of fullness after eating may indicate delayed gastric emptying. Inform your doctor if you experience these problems.
• Kidney function: Dehydration from gastrointestinal side effects (vomiting, diarrhea) at treatment initiation can impair kidney function. Patients should drink adequate fluids, particularly when starting Trulicity. Cases of acute kidney injury and worsening of chronic kidney disease have been reported, usually in association with gastrointestinal adverse events causing dehydration.
• Hypoglycemia with sulfonylureas or insulin: When Trulicity is used together with a sulfonylurea or insulin, the risk of hypoglycemia (low blood sugar) is increased. Your doctor may need to reduce the dose of these medications when Trulicity is initiated. Symptoms of hypoglycemia include headache, drowsiness, weakness, dizziness, hunger, confusion, irritability, rapid heartbeat, and sweating.
• Diabetic retinopathy: Rapid improvement in blood sugar control has been associated with temporary worsening of diabetic retinopathy. If you have diabetic retinopathy, discuss this with your doctor and ensure regular eye examinations during treatment.
• Dialysis patients: Trulicity is not recommended for patients on dialysis, as there is limited experience in this population.
• Type 1 diabetes: Trulicity is not suitable for the treatment of type 1 diabetes, as its mechanism of action requires functioning pancreatic beta cells.
• Planned surgery: If you are scheduled for surgery under general anesthesia, inform your surgeon and anesthesiologist that you are using Trulicity, as delayed gastric emptying may affect anesthetic management. Current guidelines recommend considering withholding GLP-1 receptor agonists before elective procedures.

Children and Adolescents

Trulicity has been approved for use in children and adolescents aged 10 years and older with type 2 diabetes. The recommended starting dose for pediatric patients is 0.75 mg once weekly, which may be increased to 1.5 mg once weekly after at least 4 weeks if additional glycemic control is needed. The safety and efficacy in children younger than 10 years have not been established, and Trulicity should not be used in this younger age group.

Pregnancy and Breastfeeding

Trulicity should not be used during pregnancy. The effects of dulaglutide on the developing fetus are not fully known, and animal reproduction studies have shown adverse effects at high doses. Women of childbearing potential should use effective contraception during treatment with Trulicity. If you become pregnant or plan to become pregnant, stop Trulicity and consult your doctor immediately about alternative methods of blood sugar control during pregnancy. Gestational diabetes and pre-existing diabetes in pregnancy typically require insulin-based management under close medical supervision.

Trulicity should not be used during breastfeeding. It is not known whether dulaglutide passes into human breast milk. Given the potential for adverse effects in the nursing infant, a decision should be made between discontinuing breastfeeding or discontinuing Trulicity, taking into account the importance of treatment for the mother. Discuss the benefits and risks with your doctor.

Driving and Operating Machinery

Trulicity has no or negligible direct effect on the ability to drive or use machines. However, when Trulicity is used in combination with a sulfonylurea or insulin, hypoglycemia may occur, which can impair concentration and reaction time. Avoid driving or operating machinery if you experience signs of low blood sugar. Your doctor will advise you on how to recognize and manage hypoglycemia.

Important Information About Ingredients

Trulicity contains less than 1 mmol (23 mg) of sodium per dose, making it essentially sodium-free. The formulation also contains polysorbat 80, which may cause allergic reactions in some individuals. Inform your doctor if you have any known allergies to polysorbat or related compounds. The 0.75 mg and 1.5 mg pens contain 0.10 mg polysorbat 80 per pen (0.20 mg/mL), while the 3 mg and 4.5 mg pens contain 0.125 mg per pen (0.25 mg/mL).

How Does Trulicity Interact with Other Drugs?

Trulicity, like other GLP-1 receptor agonists, slows the rate of gastric emptying. This physiological effect is part of its mechanism of action for glucose control but can theoretically delay the absorption of concomitantly administered oral medications. However, clinical pharmacology studies have demonstrated that this effect is generally modest and does not require dose adjustments for most oral medications.

In dedicated drug interaction studies, dulaglutide did not affect the pharmacokinetics of the following commonly used medications to a clinically relevant degree: metformin, sitagliptin, digoxin, lisinopril, oral contraceptives (norgestimate/ethinyl estradiol), atorvastatin, acetaminophen (paracetamol), and warfarin. These findings are reassuring for the vast majority of type 2 diabetes patients who typically take multiple medications for glucose management and cardiovascular risk factors.

Nevertheless, because of the effect on gastric emptying, patients should inform their doctor about all medications they are taking. For oral medications that require rapid absorption for clinical effect or that have a narrow therapeutic index, timing and monitoring may need to be considered.

The most clinically important interaction of Trulicity is pharmacodynamic rather than pharmacokinetic. When combined with sulfonylureas (such as glimepiride, glipizide, or glyburide) or insulin, the risk of hypoglycemia is significantly increased because both drug classes lower blood sugar through mechanisms that are not glucose-dependent. Your doctor may need to proactively reduce the dose of these medications when initiating Trulicity to minimize this risk.

For patients taking medications with a narrow therapeutic index or time-sensitive absorption profile, clinical judgment should guide whether any monitoring adjustments are needed. Always inform your healthcare provider about all prescription medications, over-the-counter drugs, vitamins, and herbal supplements you are taking before starting Trulicity.

What Is the Correct Dosage of Trulicity?

Always use Trulicity exactly as your doctor or pharmacist has instructed. Each pre-filled pen contains one weekly dose of Trulicity and is designed for single use only. The pen can be used at any time of day, with or without food. For consistency, try to inject on the same day each week. You can change the day of the week if needed, as long as at least 3 days have passed since your last injection.

Adults

Your doctor will determine the most appropriate starting dose based on your individual clinical situation. If you are starting Trulicity as monotherapy (when diet and exercise alone are insufficient and metformin is not suitable), the recommended starting dose is 0.75 mg once weekly. When adding Trulicity to existing diabetes medications, the typical starting dose is 1.5 mg once weekly.

If your blood sugar is not adequately controlled after at least 4 weeks at a given dose, your doctor may increase the dose to the next step. The dose escalation pathway is 0.75 mg → 1.5 mg → 3 mg → 4.5 mg, with each increase requiring a minimum of 4 weeks at the current dose. The maximum recommended dose is 4.5 mg once weekly.

Children and Adolescents (Age 10 and Older)

The recommended starting dose for children and adolescents aged 10 years and older is 0.75 mg once weekly. If blood sugar control is not adequate after at least 4 weeks, the dose may be increased to 1.5 mg once weekly. Higher doses (3 mg and 4.5 mg) have not been studied in pediatric patients and are not currently recommended for this age group. Trulicity has not been studied in children younger than 10 years.

Elderly Patients

No dose adjustment is required for elderly patients based on age alone. However, clinical experience in patients over 75 years is limited. Elderly patients may be more susceptible to gastrointestinal side effects and dehydration, so careful monitoring and adequate fluid intake are recommended, particularly at treatment initiation.

How to Use the Pre-Filled Pen

Trulicity is injected subcutaneously (under the skin) into one of the following body areas:

• Abdomen (belly): At least 5 cm from the navel; avoid areas with scars, bruises, or skin abnormalities.
• Front of the thigh: Upper thigh area; rotate injection sites within this region.
• Upper arm: Back of the upper arm (this site may require help from another person).

Rotate injection sites within the same body area each week. Do not inject into exactly the same spot each time. Read the Instructions for Use included with each pen carefully before your first injection. Your doctor or nurse will show you how to use the pen correctly. The pen has a one-click injection mechanism that delivers the full dose automatically.

Missed Dose

If you miss a dose and there are at least 3 days (72 hours) until your next scheduled dose, inject the missed dose as soon as possible, then resume your regular schedule. If fewer than 3 days remain before the next dose, skip the missed dose and inject the next dose on the regular day. Do not take a double dose to compensate for a missed one. If needed, you may change the day of the week you inject Trulicity, provided at least 3 days have passed since the last injection.

Overdose

If you have used more Trulicity than prescribed, contact your doctor immediately. An overdose may cause nausea, vomiting, and hypoglycemia (low blood sugar). There is no specific antidote for dulaglutide overdose. Treatment should be supportive, addressing symptoms as they arise. If hypoglycemia occurs, it should be treated according to standard clinical practice with oral glucose or intravenous dextrose as appropriate.

Stopping Treatment

Do not stop using Trulicity without first talking to your doctor. Discontinuing Trulicity may cause your blood sugar levels to rise, potentially leading to worsening of your diabetes. If you and your doctor decide to stop Trulicity, your doctor will advise you on alternative treatments to maintain adequate blood sugar control.

What Are the Side Effects of Trulicity?

Like all medicines, Trulicity can cause side effects, although not everyone will experience them. The most frequently reported adverse effects are gastrointestinal in nature and are related to the pharmacological mechanism of action of GLP-1 receptor agonists. These gastrointestinal symptoms are generally most prominent during the initial weeks of treatment and tend to diminish in frequency and intensity as treatment continues. Gradual dose escalation helps minimize these effects.

The side effect profile of Trulicity has been thoroughly characterized through the AWARD clinical trial program, post-marketing surveillance, and real-world evidence involving millions of patients worldwide. The following categorization is based on the frequency of adverse events observed in clinical trials and post-marketing reports.

Gastrointestinal side effects are the hallmark of GLP-1 receptor agonist therapy and reflect the pharmacological actions of the drug class. In clinical trials, nausea was the most common reason for treatment discontinuation, occurring in approximately 12–21% of patients depending on the dose. However, with appropriate dose titration (starting at a lower dose and gradually increasing), the incidence and severity of these effects can be substantially reduced. Most patients report that nausea, vomiting, and diarrhea are mild to moderate and resolve within the first 2–4 weeks of treatment.

Hypoglycemia is an important side effect to understand. When Trulicity is used alone or with metformin only, the risk of hypoglycemia is low because dulaglutide's insulin-stimulating effect is glucose-dependent. However, when combined with sulfonylureas or insulin, the risk is significantly higher because these agents stimulate insulin secretion independently of glucose levels. Your doctor should consider reducing the dose of sulfonylurea or insulin when starting Trulicity. Symptoms of hypoglycemia include headache, drowsiness, weakness, dizziness, hunger, confusion, irritability, rapid heartbeat, and sweating.

Heart rate increases of 2–4 beats per minute have been observed with Trulicity in clinical trials, consistent with the known pharmacology of GLP-1 receptor agonists. While this increase is generally considered clinically insignificant, patients with pre-existing cardiac arrhythmias should be monitored. The PR interval prolongation observed on ECG has not been associated with clinical symptoms in the majority of patients.

Regarding gallbladder-related events, cholelithiasis (gallstones) and cholecystitis (gallbladder inflammation) have been reported at a higher rate with GLP-1 receptor agonists compared with placebo. This may be related to the effects of weight loss and altered gastrointestinal motility. Patients should be informed about the signs and symptoms of gallbladder disease, including right upper abdominal pain, nausea, and fever.

How Should You Store Trulicity?

Proper storage of Trulicity is essential to maintain its safety and efficacy. As a biological product containing a protein-based active ingredient, dulaglutide is sensitive to temperature extremes, freezing, and prolonged light exposure, all of which can compromise the structural integrity of the molecule.

• Refrigerated storage (primary): Store Trulicity in the refrigerator at 2–8 °C (36–46 °F). This is the standard storage condition for the pre-filled pens.
• Light protection: Keep the pens in the original carton to protect from light.
• Do not freeze: Freezing damages the protein structure and renders the medication ineffective. If Trulicity has been accidentally frozen, discard it and use a new pen.
• Temporary room temperature storage: Trulicity can be taken out of the refrigerator and stored at a temperature not exceeding 30 °C (86 °F) for a single period of up to 14 days. Once removed from the refrigerator, do not return it to refrigerated storage.
• Visual inspection: Before each use, check that the solution is clear, colorless, and free of particles. Do not use the pen if the solution is cloudy, discolored, or contains visible particles, or if the pen appears damaged.
• Expiration date: Do not use Trulicity after the expiration date printed on the pen label and outer carton after “EXP.” The expiration date refers to the last day of the stated month.
• Keep out of reach of children: Store Trulicity in a safe, secure location.
• Single use only: Each pre-filled pen is for one injection only. Do not attempt to reuse pens.
• Disposal: Do not throw used pens in household waste or recycling. Dispose of them in an approved sharps container. Ask your pharmacist about proper disposal of used containers and medications you no longer need.

When traveling with Trulicity, use an insulated cooling bag to maintain appropriate temperature. Do not place the pen directly against ice or frozen cooling packs, as direct contact with extreme cold may freeze the medication. Carry Trulicity in your hand luggage during flights to avoid temperature extremes in the cargo hold. Airport security x-ray screening will not damage the medication.

What Does Trulicity Contain?

The active substance in Trulicity is dulaglutide, a recombinant fusion protein consisting of two GLP-1 analogue molecules covalently linked to a modified human IgG4 Fc fragment. Each pre-filled pen contains 0.5 mL of solution and is available in the following strengths:

The other ingredients (excipients) are:

• Sodium citrate – buffer to maintain pH stability
• Citric acid – pH adjustment
• Mannitol – tonicity agent (ensures solution is isotonic with body fluids)
• Polysorbat 80 – surfactant to prevent protein aggregation
• Water for injections – solvent

The solution for injection is clear and colorless. Each pre-filled pen is designed for single use only. Pack sizes include 2, 4, or multipacks of 12 (3 packs of 4) pre-filled pens. Not all pack sizes may be available in every country.

Trulicity is manufactured by Eli Lilly Italia S.p.A., Sesto Fiorentino, Florence, Italy, and marketed by Eli Lilly and Company, with the marketing authorization held by Eli Lilly Nederland B.V., Utrecht, Netherlands (for the European market).