Antidepressants and a GLP-1: Ozempic, Wellbutrin, Lexapro and What the Labels Say

Yes, an antidepressant and a GLP‑1 such as Ozempic, Wegovy, Mounjaro or Zepbound are routinely taken together, and none of those four labels names a single antidepressant as an interaction. People on antidepressants lost about as much weight on semaglutide as people who were not. The overlaps that matter are practical rather than chemical: two drugs that both cause nausea, a general warning about tablets absorbed through a slowed stomach, and two specific rules if your antidepressant is bupropion (Wellbutrin).

What the GLP-1 labels say about other medicines

Look for sertraline, escitalopram, fluoxetine, paroxetine, bupropion, mirtazapine or even the word antidepressant in the prescribing information for Wegovy,^[1] Zepbound,^[2] Ozempic^[3] or Mounjaro^[4] and none of them turns up. What each label does carry is one general warning about every tablet you swallow, because these drugs slow the stomach on purpose.

WEGOVY causes a delay of gastric emptying and thereby has the potential to impact the absorption of concomitantly administered oral medications. … Monitor the effects of oral medications concomitantly administered with WEGOVY.

— WEGOVY prescribing information, section 7.2

The tirzepatide labels word it more pointedly: monitor people on oral drugs “dependent on threshold concentrations for efficacy and those with a narrow therapeutic index (e.g., warfarin)”.^[2][4] Common antidepressants are not the textbook example of either. Ozempic’s label adds that, in its own clinical pharmacology studies, semaglutide made no clinically relevant difference to how well other drugs taken by mouth were absorbed.^[3]

The slowing is also strongest at the start. On Zepbound’s label, the first 5 mg dose cut the peak level of a test drug, acetaminophen, by 55% and delayed it by an hour; by week six on 15 mg there was no meaningful effect on either, and total exposure never changed.^[2] A lower, later peak with the same total is the usual pattern, and it matters most for drugs you need to work fast. A once-a-day antidepressant is not usually one of those. The broader picture for other prescriptions is in GLP-1 drugs and your other medications.

Nausea: the overlap you are most likely to feel

The most likely problem with taking both is that each one can upset your stomach. Nausea sits near the top of the side-effect list on the labels of the common SSRIs, and on the label of every GLP‑1 for weight loss.

No study has measured what happens to nausea when someone on a settled SSRI starts a GLP‑1, or starts both in the same month. In the semaglutide trials, side effects in people already on antidepressants were “generally similar” between semaglutide and placebo, in line with what the trials found in everyone else.^[11] The practical point is simple: if the nausea is bad enough that you cannot keep your antidepressant down, or you are vomiting soon after taking it, it may not be absorbed, and that is a reason to call your prescriber. Most GLP‑1 stomach trouble clusters around the first weeks and each dose increase, as covered in how long GLP-1 side effects last.

Does an antidepressant blunt GLP-1 weight loss?

In the best evidence available, no. A post hoc analysis of the STEP trials, which tested semaglutide 2.4 mg for weight loss, split participants by whether they were on an antidepressant when they started: 539 of 3,683 were. In STEP 1, people on an antidepressant lost 15.7% of their body weight on semaglutide against 0.2% on placebo; those not on one lost 14.7% against 2.8%. The other STEP trials showed the same pattern.^[11]

Antidepressants that tend to add weight

Antidepressants differ in what they do to weight. A meta-analysis of 257 placebo-controlled trials linked mirtazapine to an average gain of 1.5 kg and amitriptyline to 1.8 kg, while bupropion and fluoxetine were each linked to a loss of about 1.3 kg.^[12] Mirtazapine’s own label is direct about it: in US trials appetite rose in 17% of people against 2% on placebo, and 7.5% gained at least 7% of their body weight against none on placebo.^[13] Paroxetine’s label lists weight gain as a frequent event.^[14]

Whether a GLP‑1 cancels out that kind of weight gain is the question people most want answered, and no trial has tested it in people taking these specific drugs. The STEP analysis above is the closest evidence, and it is reassuring in general terms: being on an antidepressant did not reduce how much weight people lost. If you think your antidepressant is behind weight you gained, that is worth raising with whoever prescribes it. There are often options, and they are not for you to switch on your own.

Bupropion (Wellbutrin) and a GLP-1

Bupropion is the antidepressant with the most to say here, for three reasons. It tends to lower weight rather than raise it: in the Wellbutrin depression trials, 14% to 19% of people lost more than 5 pounds, against 6% on placebo.^[17] It is half of Contrave, the older weight-loss pill. And its label carries a seizure warning that names conditions relevant to people on weight-loss drugs.

Contrave plus Wellbutrin is ruled out

Contrave is naltrexone combined with extended-release bupropion. Its label lists as a contraindication the “use of other bupropion-containing products (including, but not limited to, WELLBUTRIN, WELLBUTRIN SR, WELLBUTRIN XL, APLENZIN and ZYBAN)”.^[18] So if you already take Wellbutrin, Contrave is not an option on top of it, and the reverse is also true. Contrave also carries the boxed warning about suicidal thoughts that applies to all antidepressants, because it contains one.^[18] We found no published trial of Contrave combined with a GLP‑1, which means taking two weight-loss drugs at once is untested.

The seizure warning

Bupropion can cause seizures, and the risk rises with dose. In studies of the sustained-release form at up to 300 mg a day, the rate was about 0.1%, or 1 in 1,000.^[17] The Wellbutrin XL label lists conditions that raise that risk, and two of them are relevant here:

Additional predisposing conditions include diabetes mellitus treated with oral hypoglycemic drugs or insulin, use of anorectic drugs, excessive use of alcohol, benzodiazepines, sedative/hypnotics, or opiates.

— WELLBUTRIN XL prescribing information, section 5.3

“Anorectic drugs” means appetite suppressants. The label does not say whether a GLP‑1 counts, and no study has measured seizure risk in people taking bupropion with a GLP‑1. The same section names hypoglycemia (low blood sugar) as a risk factor.^[17] The GLP‑1 labels put the low-blood-sugar risk on taking these drugs with insulin or a sulfonylurea, which is the same group of people the bupropion label flags.^[1][2] Bupropion is also contraindicated in anyone who has, or has ever had, a diagnosis of bulimia or anorexia nervosa, because seizures were more common in those patients; how GLP‑1 drugs interact with eating disorders is covered in GLP-1 drugs and eating disorders.^[17][18]

None of this means Wellbutrin and a GLP‑1 cannot be taken together. It means the person prescribing the GLP‑1 should know you take bupropion, its dose, and whether you are on insulin or a sulfonylurea.

Do GLP-1s cause depression or suicidal thoughts?

This is the question behind many searches about antidepressants and these drugs, and the regulatory answer changed in 2026. In January 2024 the FDA reported that its preliminary review had turned up no evidence that these drugs lead to suicidal thoughts or actions, though the agency said it was not yet able to exclude a small risk with certainty.^[6] On January 13, 2026 it finished the job. A meta-analysis of 91 placebo-controlled trials and 107,910 patients found no increase in suicidal thoughts or behavior, or in anxiety, depression, irritability or psychosis, and a Sentinel claims study of more than 2.2 million people found no increase in intentional self-harm. FDA asked for the warning to come off the Saxenda, Wegovy and Zepbound labels.^[5] The current Wegovy and Zepbound labels record it as removed in February 2026.^[1][2] Ozempic and Mounjaro never carried it.^[3][4]

Two cautions apply to anyone already treated for depression. The STEP analysis was Novo Nordisk-funded and, like most of these trials, excluded people with major psychiatric illness, so it says little about people with severe or unstable depression.^[7] And a population finding is not a guarantee about one person. The full story, including the limits of each study, is in what happened to the GLP-1 suicidal ideation warning. People with existing depression and anxiety are the subject of a Swedish cohort on worsening mental illness, and the tirzepatide-versus-semaglutide comparison is in tirzepatide versus semaglutide on mood.

FDA’s 2026 advice to clinicians still stands: if someone discloses suicidal thoughts or behavior, “refer them to mental health professionals for evaluation.”^[5] Removing a warning label does not change that.

If lithium is also on your list

Lithium is not an antidepressant, but some people take it alongside one, and it is the one mood medicine where a GLP‑1 has raised a specific flag. Lithium has a narrow margin between a working dose and a toxic one, and it depends on the kidneys and on fluid balance. A 2026 review counted six separate published reports of lithium levels rising or reaching toxicity after a GLP‑1 was started, switched or increased, and reports that the European Medicines Agency’s safety committee opened a signal in June 2026. The authors call it an uncontrolled signal rather than an established interaction, and suggest the acute cases are mostly explained by eating, drinking and fluid loss.^[19] If you take lithium, the person monitoring your levels should know before the GLP‑1 starts.

What to tell the prescriber

1. Name the antidepressant and the dose, including anything taken as needed, and say whether it is the same clinician who prescribes the GLP‑1. A telehealth GLP‑1 prescriber may not have your psychiatrist’s records.
2. Say if it is bupropion — Wellbutrin, Aplenzin, Zyban or Contrave — and whether you also take insulin or a sulfonylurea.
3. Mention lithium, if you take it, to whoever checks your levels.
4. Ask whether to space the starts if a new antidepressant and a GLP‑1 would otherwise begin in the same few weeks. No study has measured starting both at once.
5. Report mood changes promptly, better or worse. Rapid weight loss affects sleep, eating and energy, and your prescriber needs to know.
6. Do not stop the antidepressant on your own to make room for a GLP‑1, or because you read about either drug. Changes to either one should be planned with the prescriber.