Trulicity (dulaglutide): uses, side effects and what to know

Trulicity is dulaglutide, a GLP-1 receptor agonist (MedlinePlus calls the class incretin mimetics). It mimics a hormone your body releases after you eat: it helps the pancreas release insulin when blood sugar is high and slows how fast the stomach empties. MedlinePlus adds that it may lower appetite.

It is made by Eli Lilly and comes in a single-dose prefilled pen. It is a prescription medicine, but it is not a controlled substance. It is not insulin either: it works differently, although some people use it together with insulin.

According to its FDA label, Trulicity is approved for two uses:

Trulicity is injected under the skin once a week, on the same day each week, at any time of day, with or without food. Per the label, it goes in the belly, thigh or upper arm, rotating the site with each dose.

Doses on the FDA label. Adults start at 0.75 mg a week. After 4 weeks the dose may go up to 1.5 mg, and if more control is needed it can be raised in 1.5 mg steps, with at least 4 weeks on each dose, to a maximum of 4.5 mg a week. Children 10 and older start at 0.75 mg and may go up to 1.5 mg. The doctor decides your dose; do not change it on your own.

If you miss a dose: the label says to take it as soon as possible if at least 3 days (72 hours) remain before the next one. If fewer than 3 days remain, skip the missed dose and keep your usual day. Do not take two doses to make up for it.

Storing it in Puerto Rico. The label says to keep pens in the refrigerator (36°F to 46°F, or 2°C to 8°C) and never freeze them. If needed, each pen can stay at room temperature, not above 86°F (30°C), for a total of 14 days. In island heat, do not leave it in the car. For power outages, see our guide to medicines during hurricanes.

Per the FDA label, the most common Trulicity side effects involve the stomach: nausea, diarrhea, vomiting, belly pain and decreased appetite. In studies they were more frequent at the higher dose. The label raises the dose in steps to lower the risk of these stomach side effects. MedlinePlus also lists heartburn and tiredness.

Eating smaller portions and stopping when you feel full may help with nausea. If symptoms keep you from eating or drinking, tell the doctor.

Boxed warning: risk of thyroid C-cell tumors. Dulaglutide caused thyroid C-cell tumors in rats; it is unknown whether it does in people. That is why Trulicity is not used if you or a family member has had medullary thyroid carcinoma (MTC), or if you have multiple endocrine neoplasia syndrome type 2 (MEN 2). Speak up about a lump in your neck, hoarseness that won’t go away, trouble swallowing or shortness of breath.

The other warnings on the FDA label:

Contraindications. Per the label, Trulicity is not used if you have a personal or family history of medullary thyroid carcinoma, if you have MEN 2, or if you have had a serious allergic reaction to dulaglutide or any of its ingredients.

Oral medicines. Because it slows stomach emptying, Trulicity can change how other medicines you take by mouth are absorbed. The label calls for closer monitoring of those that need exact levels, such as warfarin.

Insulin and sulfonylureas. If you take them, the doctor may lower their dose when you start Trulicity to prevent low blood sugar. Tell the doctor about every medicine and supplement you take.

Pregnancy. Per the FDA label, data in pregnant people are limited and not enough to determine the risk, and animal studies showed risks to the fetus. The label says to use it in pregnancy only if the benefit justifies the risk. If you are pregnant, planning a pregnancy or become pregnant while using it, talk with the doctor.

Breastfeeding. There are no data on whether it passes into breast milk or how it affects the baby. If you breastfeed, the doctor weighs the benefits and risks with you.

Trulicity is not FDA-approved for weight loss. Its approval is for type 2 diabetes. MedlinePlus notes that it may decrease appetite and cause weight loss, but prescribing it only for that purpose is off-label use, and no one can promise you a number of pounds.

FDA-approved weight-management medicines include Wegovy (semaglutide), Zepbound (tirzepatide) and Saxenda (liraglutide). Read our semaglutide guide and our Mounjaro and Zepbound guide; Saxenda is covered in the guide to weight loss pills and medicines. If weight loss is your goal, see the weight loss evaluation. The clinic only prescribes FDA-approved brand medicines; it does not prescribe compounded GLP-1s.

Trulicity, Ozempic, Victoza and Mounjaro are all used for type 2 diabetes, but they differ in ingredient, dosing schedule and label. To see how they compare, read our Ozempic, Mounjaro, Zepbound and Wegovy comparison. If metformin is your baseline treatment, see our metformin guide.

If you take Trulicity and have severe, constant belly pain that spreads to your back, signs of a serious allergic reaction, vomiting that keeps you from holding down fluids, or low blood sugar with confusion or fainting, go to the emergency room or call 911.

If someone injected too much, call Poison Control at 1-800-222-1222. See also our emergency guide.