Skip to content

Compare

Zepbound vs Contrave

Quick read · 5 min

Last reviewed: September 2026Based on 2 clinical trialsEvery claim linked to source

Zepbound (tirzepatide, weekly injection) and Contrave (naltrexone / bupropion ER, twice-daily tablet) are both approved for weight loss in the United States. No head-to-head trial has compared these two drugs. The figures below come from separate trials, each with its own participants, length and comparison group.

At a glance

Zepbound and Contrave compared on form, trial results, cost and reported side effects
 ZepboundContrave
FormWeekly injectionTwice-daily tablet
How oftenOnce-weekly injectionTwice-daily oral tablet — no injection
Weight loss in trialsUp to 20.9% — SURMOUNT-1 (72 weeks)Up to 9.3% — COR-BMOD (56 weeks)
FDA approved20232014
Made byEli LillyCurrax Pharmaceuticals
How it worksA single molecule that activates two hunger-regulating signals in the brain — GIP and GLP-1 (both natural hormones released after eating).Bupropion activates appetite-suppressing nerve cells in the brain's hunger control centre (the hypothalamus).
Monthly cost, self-pay$299–$1,086/mowith the manufacturer savings programme; list ~$1,086$100–$400/mo
Most reported reactionNausea 31% (SURMOUNT-1)Nausea 33% (COR-I)

Every figure in this table is read from the same trial and label records used everywhere else on this site.

Weight loss in each drug's main trial

No head-to-head trial has compared these two drugs.

Zepbound(tirzepatide)20.9%

SURMOUNT-1 (72 weeks)

Contrave(naltrexone / bupropion ER)9.3%

COR-BMOD (56 weeks)

In clinical trials, participants taking tirzepatide lost on average up to 20.9% of their starting body weight, and participants taking naltrexone / bupropion ER lost on average up to 9.3%. Those numbers come from two different studies: SURMOUNT-1 enrolled 2,539 adults with obesity or overweight with comorbidities, no type 2 diabetes over 72 weeks against placebo, while COR-BMOD enrolled adults with obesity, with intensive behaviour therapy over 56 weeks against placebo + intensive behaviour therapy. Who took part, how long each trial ran and what each drug was measured against all move the percentage, so the two figures are not a measured difference between the drugs.

Monthly cost, self-pay

The bar spans the range in each drug's price record — lowest listed price to highest.

Zepbound$299–$1,086/mo

with the manufacturer savings programme; list ~$1,086

Self-pay vials via LillyDirect from $299/month (2.5 mg) to $699/month (10–15 mg), per zepbound.lilly.com on 4 September 2026; list price ~$1,086/month; $25/month copay card for eligible commercial insurance.

Contrave$100–$400/mo

~$100–$400/month (brand). Generic available in some markets.

Self-pay prices are what the manufacturer or the pharmacy lists, not what most people end up paying. Zepbound: $299–$1,086/month. Contrave: $100–$400/month. Insurance, dose and pharmacy all change both figures.

Side effects reported in the trials

Both trials reported 3 reactions in common. Each rate is the percentage of participants who reported it in the trial named beside it, so the two columns are not from the same study.

Nausea
Zepbound · SURMOUNT-131%
Contrave · COR-I33%
Constipation
Zepbound · SURMOUNT-112%
Contrave · COR-I19%
Vomiting
Zepbound · SURMOUNT-118%
Contrave · COR-I11%

A rate is the share of trial participants who reported that reaction, not a prediction for any one person.

How they differ in practice

How you take it

  • ZepboundOnce-weekly subcutaneous injection (2.5, 5, 7.5, 10, 12.5, 15 mg)
  • ContraveOral extended-release tablet, twice daily

Dose build-up

  • Contravetitrated to 32/360 mg/day over 4 weeks

Where a drug is not listed here, its prescribing information sets out its own dose steps.

How soon it acts

  • ZepboundNoticeable appetite reduction typically within 4–8 weeks; significant weight loss by 12–16 weeks
  • ContraveAppetite and craving changes typically within 4–8 weeks; significant weight loss by 16–24 weeks

Heart and metabolic findings

  • ZepboundImprovements in systolic/diastolic blood pressure, triglycerides, LDL, and HbA1c across SURMOUNT trials.
  • ContraveThe LIGHT cardiovascular outcomes trial was terminated early due to a protocol violation and did not provide a definitive answer on CV outcomes.

As stated in each drug’s trial record — not a claim about which drug protects the heart more.

Other findings recorded

  • ZepboundReduced progression to type 2 diabetes; improved sleep apnoea (SURMOUNT-OSA trial)
  • ContraveMay help specifically with emotional eating and food cravings; bupropion's antidepressant effect may be beneficial if low mood contributes to overeating

If you stop taking it

  • ZepboundIn SURMOUNT-4, participants who switched to placebo regained an average of 14.0% body weight over 52 weeks.
  • ContraveWeight regain after stopping is expected.

Common questions

Written and maintained by one person · Built with agentic AI tools · Every number checked against the cited trial · Not medical advice

How this site is built →

Next step most people take

Built with agentic AI tools and not a substitute for medical advice

Last reviewed:

Medical disclaimer: This website is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any treatment.