Three documents, three ways of counting
The US label lists adverse reactions seen in at least 5% of people on Trulicity® and more often than on placebo, from trials in which people started and stayed on 0.75 mg or 1.5 mg. [1] The EU summary sorts reactions into frequency classes. [3] Canada’s Table 2 uses a 1% threshold and counts treatment-emergent events whether or not the medicine caused them, which is why it also has a longer pool with active comparators. [4]
| Document and pool | Trulicity® 0.75 mg | Trulicity® 1.5 mg | Comparison |
|---|---|---|---|
| US Table 1, placebo-controlled pool [1] | 4.2% of 836 | 5.6% of 834 | Placebo 2.6% of 568 |
| Canada Table 2, placebo-controlled, 26 weeks [4] | 35 (4.2%) | 47 (5.6%) | Placebo 15 (2.6%) |
| Canada Table 2, studies of 26 to 104 weeks [4] | 70 of 1,671 (4.2%) | 89 of 1,671 (5.3%) | All comparators 79 of 1,844 (4.3%) |
| US Table 2, 1.5 / 3 / 4.5 mg, 36 weeks [1] | — | Below 5% in every group; not listed | No placebo arm |
| EU SmPC 4.8 [3] | “Common” (up to 1 in 10) | “Common” | — |
Reading a one-to-three-point gap
Against placebo, roughly one or two more people in every hundred on 0.75 mg reported tiredness, and about three more on 1.5 mg. [1] In the longer Canadian pool the 1.5 mg figure sits only a point above the comparator groups, which included other diabetes medicines rather than placebo alone. [4] Most people on Trulicity® in these trials did not report fatigue at all.
The labels are silent on when tiredness starts, how long it lasts and whether it led anyone to stop treatment. Section 8.5 of the US label reports no overall safety differences in adults aged 65 and over, and the paediatric trial matched the adult profile except at the injection site; neither gives a separate fatigue figure. [1]
What studies of dulaglutide add
Very little. A PubMed search on 20 October 2026 for dulaglutide together with fatigue or asthenia found no trial analysis devoted to tiredness. The one relevant result is a retrospective, single-arm cohort of 205 adults treated with dulaglutide 1.5 mg at a clinic in Riyadh, in which 28% reported fatigue and 52% nausea when interviewed by phone. [5]
That figure is far higher than the trial rates, but the design explains much of the gap: there was no comparison group, the answers relied on memory, and many participants had long-standing diabetes and severe obesity, both of which can cause tiredness on their own. [5][6][7] It shows that fatigue is something people on dulaglutide mention, not how often the medicine causes it.
How Trulicity® could leave you drained
- Low blood sugar (supported by the label): with insulin or a sulfonylurea, lows become far more frequent, and the US guide lists weakness and drowsiness among their signs. [1][2] The Trulicity® low blood sugar page sets out the rates for each combination.
- Fluid loss (supported by the label): nausea, vomiting and diarrhoea are the most frequent reactions, and the label links dehydration from them to kidney injury. [1] MedlinePlus lists listlessness among signs of severe dehydration, and Cleveland Clinic notes that dehydration can cause fatigue. [7][8]
- Eating less (plausible, not measured): decreased appetite was reported by 8.6% on 1.5 mg against 1.6% on placebo, but the label never connects it with tiredness. [1] MedlinePlus counts malnutrition among causes of fatigue. [6]
- Heart rhythm (rare, but urgent): Trulicity® lengthens the PR interval slightly, which Canada notes has been associated with atrial fibrillation, and its patient information lists fatigue with palpitations or breathlessness as a reason to stop and seek help at once. [4]
Everyday causes worth ruling out
MedlinePlus separates fatigue, a lack of energy and motivation, from drowsiness, the need to sleep. [6] It lists common causes that have nothing to do with Trulicity®: anaemia and iron deficiency, depression or grief, sleep problems such as insomnia or sleep apnoea, an underactive or overactive thyroid, persistent pain, and alcohol. [6] Diabetes itself, kidney disease, heart failure and infections are on the same list. [6]
Other medicines matter too. MedlinePlus names blood pressure medicines, diuretics, sleeping pills, steroids and allergy antihistamines, and Cleveland Clinic adds low vitamin B12 or vitamin D. [6][7] Many people starting Trulicity® take several of these, so a full medicine review is often more revealing than the timing of the injection.
Things the guidance suggests
MedlinePlus suggests regular sleep, a balanced diet with enough water through the day, regular exercise, ways to relax and a manageable schedule, and avoiding alcohol and nicotine. [6] It notes that caffeine and other stimulants do not treat fatigue and can make it worse when stopped, and that no medicine should be stopped or changed without talking to your provider. [6]
When stomach effects are cutting into meals, a 2025 Mayo Clinic review for primary care suggests smaller, more frequent meals, enough fluids and fewer high-fat or very sugary foods, and the Trulicity® guide stresses drinking fluids to lower the chance of dehydration. [2][11] If you use insulin or a sulfonylurea, checking your glucose during a tired spell tells you whether a low is involved. [2][9]
Trulicity® is a registered trademark of Eli Lilly and Company. PepLabo is not affiliated with or endorsed by Eli Lilly and Company.
When to get help
The signs and contact information below come from this article’s sourced guidance.
Emergency
- Tiredness with palpitations, an irregular heartbeat or shortness of breath
Contact: Stop Trulicity® and get medical help right away
- Fatigue with chest, arm or upper back pain
Contact: Emergency services (911 / 112)
Cleveland Clinic [7]
- Weakness or drowsiness with sweating, shakiness or confusion while using insulin or a sulfonylurea
Contact: Treat low blood sugar as you were taught; emergency care if it does not improve