Trulicity (Dulaglutide): How It Works for Type 2 Diabetes
Trulicity works by turning on the GLP-1 receptor, so the pancreas releases more insulin only when blood sugar is high. Its drug, dulaglutide, is two GLP-1 pieces joined to the stem of a human antibody, which makes it big enough to last about 5 days in the body.
Eli Lilly makes it. US doctors prescribe it for type 2 diabetes in adults and children 10 and older. It is also used to lower heart risk in some adults with type 2 diabetes. It is not approved for weight loss.
Key facts
What it is: Dulaglutide, a GLP-1 receptor agonist. It is a fusion protein: two copies of a GLP-1 piece, each tied to the Fc stem of a human antibody.
Why it lasts: At about 63 kilodaltons it is large, and that size slows clearance. Half of it is gone after about 5 days.
What it does: Pushes insulin up only while blood sugar is high, holds glucagon down, and slows the stomach.
Where it stands on 8 November 2026: A US prescription medicine from Eli Lilly. Approved for type 2 diabetes from age 10 and for heart risk in some adults. Not on FDA's drug shortage list.
Sources: Trulicity prescribing information, DailyMed; EMA assessment report on Trulicity, 2014; Drugs@FDA data for BLA 125469 (openFDA); FDA drug shortage list
How is Trulicity built?
Trulicity is built from three parts, and the whole thing comes as a pair. The FDA label calls dulaglutide a fusion protein: two matching chains held together by disulfide bonds. Each chain starts with a GLP-1 piece, then a small linker, then the Fc part of a changed human antibody of the IgG4 type.
| Part | What it is | Why it is there |
|---|---|---|
| 1. The GLP-1 piece (the key) | A copy of the gut hormone GLP-1, 90% matched to the human form. Three building blocks are swapped, at positions 8, 22 and 36. | It turns on the GLP-1 receptor. The swaps help it resist the enzyme DPP-4 and make an immune reaction less likely. |
| 2. The linker | A short made-up chain of 16 amino acids. | It ties the GLP-1 piece to the antibody stem. |
| 3. The Fc stem (the keyring) | The Fc part of a human IgG4 antibody, edited by Lilly. | Its size slows how fast the body clears the drug. The edits stop it from splitting into half antibodies and make it less likely to bind the Fc receptors on immune cells. |
| Two of everything | Two identical chains, each with all three parts, joined by disulfide bonds. | So each molecule carries two GLP-1 pieces. |
The three swaps. The European chemical name spells them out: glycine at position 8, glutamic acid at position 22 and glycine at position 36. The European regulator says the swaps were made to protect the drug from DPP-4 and to lower the chance that the immune system reacts to it. It does not say which single swap does which job, so neither do we.
Grown, not mixed. Most peptide drugs are short chains that chemists build one amino acid at a time. Many short peptides come as a dry powder in a vial, the kind our peptide reconstitution calculator deals with. Dulaglutide is far too large for that. It is made by living cells grown in culture, from the Chinese hamster ovary line.
Where it started. Scientists at Lilly Research Laboratories described it in 2010 under the code name LY2189265, a GLP-1 and IgG4 Fc fusion protein. In lab tests it switched the receptor on fully, and in rats and monkeys it lasted 1.5 to 2 days, far longer than natural GLP-1.
Sources: Trulicity prescribing information, DailyMed; EMA assessment report on Trulicity, 2014; Glaesner et al., LY2189265 paper, 2010
Why does Trulicity last so long?
Trulicity lasts for days because it is big. Natural GLP-1 lasts only 90 to 120 seconds in the blood, mostly because DPP-4 cuts off its front end. Dulaglutide guards against that cut, and then its antibody stem does the rest. The European regulator says the Fc part makes the molecule bigger, which slows how fast the body clears it.
Its half-life, the time it takes for half the drug to clear, is about 5 days in the FDA label. The European report gives about 4.7 days. In the end, the body is thought to break it down like any other protein, into its amino acids.
Size versus a fatty tail. Semaglutide, the drug in Ozempic, solves the same problem another way. It is a small peptide of about 4.1 kilodaltons with a fatty tail that grips albumin, a carrier protein in blood. Dulaglutide, at about 63 kilodaltons, is roughly 15 times heavier. That ratio is our own math from the two FDA labels. The two designs end up in a similar place: about 5 days for one, about a week for the other.
| Trait | Dulaglutide (Trulicity) | Semaglutide (Ozempic) |
|---|---|---|
| How it lasts | Sheer size: a big antibody stem slows clearance | A fatty tail grips albumin, a carrier protein in blood |
| Size | About 63 kilodaltons | About 4.1 kilodaltons (4,113.58 g/mol) |
| Half-life | About 5 days (EMA estimate 4.7 days) | About 1 week |
| Match to human GLP-1 | 90% | 94% |
| Made in | Chinese hamster ovary cells | Yeast makes the peptide backbone |
| Defense against DPP-4 | Swapped building blocks in the GLP-1 piece | A change at position 8 |
The fatty tail trick, and how it lets semaglutide survive even as a tablet, is the subject of our oral semaglutide episode. For the vial arithmetic behind the semaglutide shot, there is a semaglutide reconstitution calculator.
Sources: EMA assessment report on Trulicity, 2014; Trulicity prescribing information, DailyMed; Ozempic prescribing information, FDA, May 2026
What does Trulicity do in the body?
Trulicity does three main things, all through the GLP-1 receptor. That receptor sits on the surface of the beta cells in the pancreas, the cells that make insulin.
1. More insulin, but only when needed. When dulaglutide binds, it raises a messenger inside the cell called cyclic AMP (cAMP). That leads to insulin release that depends on glucose: more insulin when blood sugar is high, less push when it is not. The label reports that both the fast first wave and the slower second wave of insulin release went up in people with type 2 diabetes.
2. Less glucagon. Glucagon is the hormone that tells the liver to put sugar into the blood. Dulaglutide lowers how much is released.
3. A slower stomach. Food moves on from the stomach more slowly. According to the label, this delay is largest at the start and shrinks over time.
Together these lower blood sugar both before and after meals. Because the stomach slows, the label says it could change how fast other swallowed medicines are absorbed. In the label's drug interaction studies, though, the tested pills were not affected in a way that mattered.
Who is Trulicity approved for?
Trulicity is approved in the US for two uses, both in type 2 diabetes. First, alongside diet and exercise, to improve blood sugar in adults and in children 10 years and older. Second, to lower the risk of a major heart event (heart attack, stroke or heart-related death) in adults with type 2 diabetes who have heart disease or several heart risk factors.
- 18 September 2014: first FDA approval, as a biologic and a new molecular entity (BLA 125469).
- 21 November 2014: approved across the European Union.
- 21 February 2020: the heart risk use is added, based on the REWIND trial.
- 17 November 2022: the blood sugar use widens to children 10 and older.
- 12 March 2026: the newest safety change, covered in the side effects section below.
The children's approval rests on AWARD-PEDS, a 26-week trial in 154 young people aged 10 to 17. On placebo, HbA1c, a three-month average of blood sugar, rose by 0.6 points. On dulaglutide it fell. About half of those on dulaglutide (51%) got below 7.0%, against 14% on placebo. The change in body mass index did not differ between the groups. In Europe, the regulator also lists Trulicity for adults and children from 10 years.
Not a weight loss drug. Weight is not one of its approved uses, and Lilly's own Trulicity site says so in those words. In Lilly's diabetes studies, average weight change ran from a small gain to a loss of about 10 pounds.
Sources: Trulicity prescribing information, DailyMed; FDA approval letter, 18 September 2014; EMA Trulicity medicine page; FDA heart use letter, 21 February 2020; FDA letter on children 10 and up, 17 November 2022; FDA label change letter, 12 March 2026; AWARD-PEDS, New England Journal of Medicine 2022; Lilly Trulicity patient site
What did the REWIND trial find?
REWIND found about 12% fewer heart attacks, strokes and heart-related deaths on dulaglutide than on placebo, on average. Over a median of 5.4 years, the main event hit 12.0% of the dulaglutide group and 13.4% of the placebo group. That is a gap of 1.4 percentage points, and a hazard ratio of 0.88.
Who was in it. The trial enrolled 9,901 adults aged 50 or older with type 2 diabetes, at 371 sites in 24 countries, between August 2011 and August 2013. Neither patients nor doctors knew who got the drug. The average age was 66, and the median HbA1c was 7.2%. Just 31.5% had known heart disease. Most of the rest, 62.8%, had risk factors only. That makes REWIND mostly a prevention trial. Its authors note that the earlier GLP-1 heart trials showing a benefit had enrolled people at high heart risk with higher HbA1c.
| Outcome | Dulaglutide (4,949) | Placebo (4,952) | Hazard ratio |
|---|---|---|---|
| Heart attack, stroke or heart-related death (main result) | 12.0% | 13.4% | 0.88 (0.79 to 0.99) |
| Heart-related death | 6.4% | 7.0% | 0.91 (0.78 to 1.06) |
| Non-fatal heart attack | 4.1% | 4.3% | 0.96 (0.79 to 1.16) |
| Non-fatal stroke | 2.7% | 3.5% | 0.76 (0.61 to 0.95) |
| Death from any cause | 10.8% | 12.0% | 0.90 (0.80 to 1.01) |
How to read the table. Only the first row was the trial's main test, and it passed. The FDA label says the three parts are shown for support only, so no firm claim should be made about each one alone. Death from any cause was lower on paper, but the range crosses 1.0, so the trial did not show a clear difference.
Gut side effects were common: 47.4% on dulaglutide against 34.1% on placebo. Eli Lilly paid for the trial. These are averages for large groups, not a promise for any one person.
Sources: REWIND, The Lancet 2019; Trulicity prescribing information, DailyMed; FDA heart use letter, 21 February 2020
Trulicity vs tirzepatide: what did SURPASS-CVOT show?
In SURPASS-CVOT, tirzepatide proved no worse than Trulicity at preventing heart events, but it did not prove better. The trial put 13,299 adults with type 2 diabetes and artery-related heart disease on one drug or the other, without telling them which. The authors describe Trulicity as a drug already shown to lower heart events.
Among the 13,165 people in the main analysis, heart attack, stroke or heart-related death hit 12.2% on tirzepatide and 13.1% on dulaglutide. The hazard ratio was 0.92, with a range of 0.83 to 1.01. The test for "no worse" passed, and the test for "better" did not. Gut side effects were more common on tirzepatide. Eli Lilly, which makes both drugs, paid for it.
The Mounjaro label adds a detail the journal summary leaves out: people were followed for a median of 210.1 weeks, about 4 years. Mounjaro is the diabetes brand of tirzepatide. Based on this trial, the FDA approved a heart risk use for it on 27 August 2026, for high-risk adults with type 2 diabetes.
Tirzepatide is a different kind of key. It turns on the GLP-1 receptor and a second one for the hormone GIP, as the first Molecule Mechanics episode shows. Its vial math has a page of its own, the tirzepatide reconstitution calculator.
Sources: SURPASS-CVOT, New England Journal of Medicine 2025; Mounjaro prescribing information, FDA, August 2026; Drugs@FDA record for NDA 215866
Trulicity vs Ozempic: how are they different?
Trulicity and Ozempic both turn on the GLP-1 receptor and both treat type 2 diabetes, but the drugs inside are built in very different ways. Ozempic holds semaglutide from Novo Nordisk, a small peptide with a fatty tail. Trulicity holds dulaglutide from Eli Lilly, a large protein on an antibody stem. The table puts them next to tirzepatide.
| Trulicity | Ozempic | Mounjaro | |
|---|---|---|---|
| Drug inside | Dulaglutide | Semaglutide | Tirzepatide |
| Maker | Eli Lilly | Novo Nordisk | Eli Lilly |
| Receptors it turns on | GLP-1 | GLP-1 | GLP-1 and GIP |
| First US approval | 2014 | 2017 | 2022 |
| Blood sugar use | Adults and children 10 and older with type 2 diabetes | Adults with type 2 diabetes | Adults and children 10 and older with type 2 diabetes |
| Heart use | Adults with type 2 diabetes and heart disease or several risk factors | Adults with type 2 diabetes and heart disease | Adults with type 2 diabetes at high risk, approved 27 August 2026 |
| Kidney use | None | Adults with type 2 diabetes and chronic kidney disease | None |
Head to head. SUSTAIN 7 tested semaglutide against dulaglutide in 1,201 adults with type 2 diabetes already on metformin, for 40 weeks at 194 sites in 16 countries. Everyone knew which drug they had. It compared two pairings of the drugs. In both, semaglutide did more. HbA1c fell by 1.5 to 1.8 points, against 1.1 to 1.4. Weight fell by 4.6 to 6.5 kg, against 2.3 to 3.0 kg. Gut problems were the most common side effect in every group. Novo Nordisk, the maker of Ozempic, paid for it.
Which one suits a person is a question for their prescriber, not a trial table. For the history of the whole drug family, from exenatide to the newest pills, see our explainer What is GLP-1?
Sources: Ozempic prescribing information, FDA, May 2026; Trulicity prescribing information, DailyMed; Mounjaro prescribing information, FDA, August 2026; SUSTAIN 7, Lancet Diabetes and Endocrinology 2018
What are the side effects of Trulicity?
The most common side effects of Trulicity are in the gut. The label names nausea, diarrhea, vomiting, belly pain and decreased appetite as the reactions that 5% or more of people had.
Boxed warning. This is the FDA's strongest kind of warning. Dulaglutide caused thyroid C-cell tumors in rats, and nobody knows whether it does the same in people. So it must not be used by anyone with a personal or family history of medullary thyroid cancer. Having MEN 2, an inherited condition also called multiple endocrine neoplasia type 2, rules it out too. It also must not be used after a serious allergic reaction to dulaglutide or its ingredients.
Other warnings on the label:
- Pancreatitis (inflammation of the pancreas).
- Low blood sugar when it is used with insulin or with pills that push insulin out, such as sulfonylureas.
- Serious allergic reactions, such as anaphylaxis and angioedema, a deep swelling under the skin.
- Kidney injury from losing fluid through vomiting or diarrhea.
- Severe gut reactions. It is not recommended for people with severe gastroparesis.
- Diabetic eye problems. In REWIND they happened in 1.9% on dulaglutide against 1.5% on placebo.
- Gallbladder disease.
- Breathing stomach contents into the lungs during anesthesia or deep sedation.
The March 2026 change. In April 2025 the FDA flagged a possible safety signal for the whole GLP-1 class: blocked bowels. On 12 March 2026 it approved new Trulicity wording. Intestinal obstruction and severe constipation, including stool stuck hard in the bowel, now appear in the list of problems reported after approval. Reports like these come in by choice. So the label says there is no way to tell how often they happen, or to prove the drug caused them.
Two quieter label facts. Average heart rate in adults rose by 2 to 4 beats a minute. And because dulaglutide is a large protein, the body can make antibodies to it. In the diabetes trials, 64 of 3,907 adults (1.6%) did. The label found no clear effect on how the drug worked or on its safety.
Whether these risks matter for one person is for their own doctor to weigh.
Sources: Trulicity prescribing information, DailyMed; FDA label change letter, 12 March 2026; REWIND, The Lancet 2019
Is Trulicity still available, and is it FDA approved?
Yes on both counts, as of 8 November 2026. FDA data updated on 6 November 2026 list every Trulicity product as a prescription drug under Eli Lilly's application, the only dulaglutide application in that data. The current label on DailyMed is version 62, published 10 August 2026, and it carries the March 2026 revision.
FDA's drug shortage list, updated 6 November 2026, does not include dulaglutide. That is a check on one day, not a promise about later supply. Our medical review policy explains how status facts like these are checked before a page goes up.
Sources: Drugs@FDA data for BLA 125469 (openFDA); DailyMed label version history; FDA drug shortage list
What else do people ask about Trulicity?
What is Trulicity?+
Trulicity is the brand name for dulaglutide, a prescription GLP-1 receptor agonist made by Eli Lilly and first approved by the FDA on 18 September 2014. It is a protein drug, grown in cells, that joins two copies of a GLP-1 look-alike to part of a human antibody.
What is Trulicity dulaglutide injection used for?+
It has two US uses, both in type 2 diabetes. Alongside diet and exercise, it improves blood sugar in adults and in children 10 and older. It also lowers the risk of heart attack, stroke and heart-related death in adults with type 2 diabetes who have heart disease or several heart risk factors. It is not approved for type 1 diabetes or for weight loss.
Is Trulicity insulin?+
No. Trulicity is a GLP-1 receptor agonist, not insulin. It helps the pancreas release more of its own insulin, and only when blood sugar is high. Lilly puts it as helping the body release the insulin it still makes. Because insulin and pills such as sulfonylureas also lower blood sugar, the label warns that using Trulicity with them raises the chance of low blood sugar.
Can Trulicity be used for weight loss?+
No, weight loss is not an approved use. In the US, Trulicity is approved for type 2 diabetes and heart risk only, and Lilly says plainly that it is not a weight loss drug. In Lilly studies with other diabetes medicines, average weight change in adults ranged from a gain of 0.4 lb to a loss of about 10 lb. In the trial in children, weight did not change differently from placebo. These are group averages, not a forecast for anyone.
Is Trulicity the same as Ozempic?+
No. Both turn on the GLP-1 receptor and both treat type 2 diabetes, but they hold different drugs from different companies. Ozempic is semaglutide from Novo Nordisk, a small peptide with a fatty tail. Trulicity is dulaglutide from Eli Lilly, a large protein built on an antibody stem. In the SUSTAIN 7 trial, which Novo Nordisk funded, semaglutide lowered blood sugar and weight more than dulaglutide.
What are the most common side effects of Trulicity?+
Nausea, diarrhea, vomiting, belly pain and lower appetite top the label list, each reported by 5% or more of people. In REWIND, gut side effects were reported by 47.4% of people on dulaglutide against 34.1% on placebo over about five years.
How quickly does Trulicity start working?+
Lilly says Trulicity starts lowering blood sugar from the very first use. The label says the drug reaches its peak in the blood 24 to 72 hours after each use, and blood levels settle after 2 to 4 weeks. The label's trials measured HbA1c after 24 weeks or more. HbA1c is a blood test that reflects average blood sugar over recent months, so the effect on that number takes months to show.
What are the cons of Trulicity?+
The main downsides in the sources are common gut side effects and the boxed warning, since dulaglutide caused thyroid C-cell tumors in rats. It needs a prescription and is not approved for weight loss. In the SUSTAIN 7 trial, semaglutide lowered blood sugar and weight more than dulaglutide did. Its heart benefit in REWIND was real but modest, about 1.4 fewer events per 100 people over 5.4 years. Some people also make antibodies to it, though the label found no clear effect from them.
Who should not use Trulicity?+
The label rules it out for three groups. The first is anyone with a personal or family history of medullary thyroid cancer. The second is anyone with MEN 2. The third is anyone who has had a serious allergic reaction to dulaglutide or its other ingredients. It is not recommended for people with severe gastroparesis, a condition where the stomach empties very slowly. It is not known whether it is safe and effective in children under 10.
Is Trulicity approved for children?+
Yes, for type 2 diabetes from age 10. The FDA widened the blood sugar use on 17 November 2022, based on AWARD-PEDS. In that 26-week trial of 154 youths, 51% of those on dulaglutide reached an HbA1c under 7.0%, against 14% on placebo. The heart risk use is for adults only.
Is there a Trulicity shortage?+
Not on FDA's current list. We checked FDA's drug shortage list on 8 November 2026 (page updated 6 November 2026), and dulaglutide was not on it. That is a snapshot of one day, not a promise about supply later on.
Is Trulicity a GLP-1?+
Yes. The label calls dulaglutide a GLP-1 receptor agonist, the same drug class as semaglutide and exenatide. Tirzepatide also turns on the GLP-1 receptor, plus a second receptor for the hormone GIP.
What class of medication does dulaglutide belong to?+
Dulaglutide belongs to the GLP-1 receptor agonist class, which is the term its FDA label uses. It is also a biologic. It is a fusion protein grown in Chinese hamster ovary cells, and the FDA licensed it under biologics license application 125469 rather than as an ordinary new drug. Semaglutide (Ozempic) and exenatide (Byetta) belong to the same class.
Does Trulicity cause nausea?+
Yes, it can. Nausea comes first on the label list of reactions seen in at least 5% of people, ahead of diarrhea, vomiting, belly pain and lower appetite. Across roughly five years of REWIND, gut complaints showed up in 47.4% of the dulaglutide group versus 34.1% with placebo. The label does not recommend it for severe gastroparesis, and since March 2026 it also lists bowel blockage and severe constipation among reports after approval. Nausea that does not settle is worth raising with the prescriber.
How does Trulicity work?+
Trulicity works through the GLP-1 receptor on the insulin-making cells of the pancreas. When blood sugar climbs, it prompts those cells to put out more insulin and holds back glucagon, a hormone that pushes sugar up, and the push eases again as sugar comes down. It also slows how quickly the stomach empties after a meal. Its bulky antibody stem keeps it circulating for days, long after a natural GLP-1 molecule would be gone.
Sources: Trulicity prescribing information, DailyMed; FDA approval letter, 18 September 2014; Lilly Trulicity patient site; Ozempic prescribing information, FDA, May 2026; SUSTAIN 7, Lancet Diabetes and Endocrinology 2018; REWIND, The Lancet 2019; AWARD-PEDS, New England Journal of Medicine 2022; FDA letter on children 10 and up, 17 November 2022; FDA drug shortage list; Mounjaro prescribing information, FDA, August 2026; Drugs@FDA data for BLA 125469 (openFDA); FDA label change letter, 12 March 2026; Drugs@FDA data for exenatide (openFDA)
What did we learn about Trulicity?
Trulicity is two GLP-1 keys on an antibody keyring. Three swapped building blocks shield each key from DPP-4, and the heavy Fc stem keeps the whole molecule in the blood for days. Once there, it boosts insulin only when blood sugar runs high, holds back glucagon and slows the stomach. REWIND showed a modest drop in heart events in a mostly prevention group, and tirzepatide later matched it on heart events without beating it.
Molecule Mechanics is a YouTube series that animates how peptide and protein drugs are built and what the research on them shows. It never tells anyone what to take. An AI voice from ElevenLabs reads the script, the drawings are original, and each episode's sources sit in its YouTube description. Earlier episodes include tirzepatide, cagrilintide and oral semaglutide.
Exenatide, sold as Byetta from 2005 and now listed by the FDA as discontinued, is covered in our exenatide article. One of the newest drugs in this family, retatrutide, is still experimental, and it has a page of its own here: the retatrutide calculator. If you spot a mistake on this page, you can report it under our corrections policy.
See every Molecule Mechanics video
Sources: Molecule Mechanics channel; Drugs@FDA data for exenatide (openFDA)
Learning only, not medical advice. This page retells what the Trulicity label, regulators and published trials report. A decision about any prescription medicine belongs to a person and their own clinician.