What each drug is

Wegovy is made by Novo Nordisk. Its active ingredient is semaglutide. It is FDA-approved for chronic weight management in adults and teens with obesity, and for lowering heart risk in adults with heart disease and excess weight.

Trulicity is made by Eli Lilly. Its active ingredient is dulaglutide. It is FDA-approved for type 2 diabetes and for lowering heart risk in people with type 2 diabetes. It is not approved for weight loss.

Both copy the gut hormone GLP-1, so they work in similar ways. They lower appetite, slow the stomach, and help the pancreas release insulin when blood sugar is high. The difference is how strong each one is and what dose the maker studied.

Head-to-head weight loss

The best comparison comes from a trial called SUSTAIN 7, which pitted semaglutide against dulaglutide in people with type 2 diabetes. At the higher doses, people on semaglutide lost about 14 pounds on average over 40 weeks. People on dulaglutide lost about 7 pounds. Semaglutide also lowered blood sugar more.

Keep in mind that trial used Ozempic-level doses of semaglutide (up to 1 mg). Wegovy goes up to 2.4 mg, which produces much more weight loss. In the STEP 1 trial, people without diabetes lost about 15 percent of their body weight on Wegovy over 68 weeks. There is no Trulicity trial that comes close to that.

In short, semaglutide is the stronger drug for weight loss, and Wegovy is the dose built for it.

Side effects

Both drugs share the same list of common side effects: nausea, vomiting, diarrhea, constipation, and belly pain. Both carry the same boxed warning about thyroid tumors seen in rodents, and both should be avoided by people with a family history of medullary thyroid cancer.

Because Wegovy is a higher dose, stomach side effects tend to be more frequent than with Trulicity. In SUSTAIN 7, nausea was reported by about 22 percent of people on semaglutide 1 mg versus about 20 percent on dulaglutide 1.5 mg, so at matched doses they were similar.

Dosing and the pen

Both are once-weekly shots under the skin. Trulicity comes in a single-use pen with a hidden needle that many people find easy. Doses are 0.75, 1.5, 3, and 4.5 mg.

Wegovy also comes in single-use pens. The dose climbs over about 16 to 20 weeks from 0.25 mg up to 2.4 mg. The slow climb is built in to limit nausea.

Which one is right for you?

If your main goal is weight loss and you do not have diabetes, Trulicity is not the right tool. It is not approved for that, and it does not produce much weight loss.

If you have type 2 diabetes and want blood sugar control with some weight loss, both are options. Semaglutide (as Ozempic) usually wins on both counts, but some insurance plans cover one and not the other, and some people simply tolerate one better.

If you have heart disease, both have shown heart benefits in large trials. Your prescriber will weigh your full history.

The Zen IV Spa approach

Zen IV Spa does not prescribe brand Wegovy or Trulicity. We prescribe compounded semaglutide, the same active ingredient as Wegovy, for $199 per month, and compounded tirzepatide for $299 per month. Compounded drugs are made by a licensed pharmacy for a specific patient and are not FDA-approved products.

Your first video visit with our medical director is free, and a nurse draws labs at your home anywhere in New York and New Jersey. If you have been on Trulicity and want more weight loss, we can review whether a switch makes sense. Start at /weight-loss/.

Common Questions

Is Trulicity approved for weight loss?+

No. Trulicity (dulaglutide) is approved for type 2 diabetes and heart-risk reduction. Wegovy (semaglutide) is approved for weight loss.

Which causes more weight loss, Wegovy or Trulicity?+

Wegovy, by a wide margin. In a head-to-head diabetes trial, semaglutide produced about twice the weight loss of dulaglutide, and Wegovy uses an even higher dose.

Can I switch from Trulicity to Wegovy?+

Yes, with a prescriber's guidance. You would usually stop Trulicity and start at the lowest Wegovy dose, then climb.

Are the side effects the same?+

The list is the same: nausea, vomiting, diarrhea, constipation. Higher doses of semaglutide tend to cause more stomach symptoms.

Does Zen IV Spa offer Trulicity?+

No. We prescribe compounded semaglutide and compounded tirzepatide, which are not FDA-approved but contain the same active ingredients as Wegovy and Zepbound.

Which is better for diabetes?+

In SUSTAIN 7, semaglutide lowered blood sugar more than dulaglutide. Both help, and insurance coverage often decides.

Sources: FDA prescribing information for Wegovy (semaglutide) and Trulicity (dulaglutide), 2024; SUSTAIN 7 trial, Pratley et al., Lancet Diabetes & Endocrinology 2018; STEP 1 trial, NEJM 2021.

All treatments are medical services. Every guest is screened, and every treatment is prescribed by a licensed provider. Nothing on this page is medical advice for you personally, and the opinions summarized here belong to the doctors named, not to Zen IV Spa. Talk to a provider before starting or stopping anything.