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Contrave logoContrave
vs
Mounjaro logoMounjaro

Contrave vs Mounjaro

Contrave and Mounjaro differ in nearly every way. Contrave is a daily oral tablet combining naltrexone and bupropion at $150-200/month, producing ~5-8% weight loss. Mounjaro is a weekly injection (tirzepatide) at $395+/month, producing ~21% weight loss. The choice often comes down to injection tolerance, budget, and how much weight loss is needed.

Contrave: ~5-8% avg. loss
Mounjaro: ~21% avg. loss
Contrave cost: $150-200 private
Mounjaro cost: From $395 private

Compare Contrave vs Mounjaro at a Glance

 ContraveMounjaro
Drug classOpioid antagonist + NDRI combinationDual GIP/GLP-1 receptor agonist
How takenDaily oral tabletsWeekly injection
Avg. weight loss~5-8%~21%
First approved2014 (FDA), 2019 (TGA)2022 (FDA), 2023 (TGA)
AU cost/month$150-200 privateFrom $395 private
PBS statusNoNo
Prescription needed?YesYes
AU supply statusNo issuesStable

Compare Contrave vs Mounjaro Cost in Australia

Contrave: $150-200 private

Mounjaro: From $395 private

Compare Contrave vs Mounjaro Weight Loss Efficacy

Contrave Clinical Trials

COR-I

6.1% weight loss vs 1.3% placebo

56 weeksn=1,742

COR-II

6.4% weight loss maintained

56 weeks

COR-BMOD

9.3% with intensive behaviour modification

56 weeks

Mounjaro Clinical Trials

SURMOUNT-1

20.9% weight loss (15mg)

72 weeksn=2,539

SURMOUNT-2

15.7% weight loss (diabetes pop.)

72 weeks

SURMOUNT-3

25.3% weight loss (with lifestyle intervention)

88 weeks

SURMOUNT-OSA

Significant improvement in sleep apnoea

52 weeks

Clinical trial data at highest approved doses. Individual results vary.

Compare Contrave vs Mounjaro Side Effects

Contrave

Very common

  • Nausea (32%)
  • Constipation (18%)
  • Headache (14%)

Common

  • Vomiting
  • Dizziness
  • Insomnia
  • Dry mouth
  • Diarrhoea

Serious (rare)

  • Seizures (contraindicated in seizure disorders)
  • Increased blood pressure
  • Hepatotoxicity
  • Suicidal thoughts (bupropion, young adults)
  • Cannot be used with opioids

Mounjaro

Very common

  • Nausea (up to 33%)
  • Diarrhoea (up to 23%)
  • Decreased appetite

Common

  • Vomiting
  • Constipation
  • Abdominal pain
  • Dyspepsia
  • Injection site reactions

Serious (rare)

  • Pancreatitis
  • Hypoglycaemia (with insulin)
  • Gallbladder disease
  • Thyroid tumour risk (animal data)
  • May reduce effectiveness of oral contraceptives

Compare How Contrave and Mounjaro Work

Contrave

Opioid antagonist + NDRI combination

Targets two brain pathways. Naltrexone (opioid antagonist) blocks reward/craving pathways in the mesolimbic dopamine circuit. Bupropion (NDRI) acts on the hypothalamic appetite centre to reduce hunger. The combination addresses both biological hunger drive and reward-based food cravings.

Mounjaro

Dual GIP/GLP-1 receptor agonist

First dual-agonist: targets both GIP and GLP-1 receptors simultaneously. This dual mechanism produces greater weight loss than GLP-1-only drugs. Reduces appetite, slows gastric emptying, improves insulin sensitivity, with additional metabolic benefits through the GIP pathway.

Compare Contrave vs Mounjaro Dosing Schedule

Contrave

Daily oral tablets

DosePeriodNote
1 tab morningWeek 1Starting dose
1 AM + 1 PMWeek 2Escalation
2 AM + 1 PMWeek 3Escalation
2 AM + 2 PMWeek 4+Maintenance (4 tablets/day)

Mounjaro

Weekly injection

DosePeriodNote
2.5mgWeeks 1-4Starting dose
5mgWeeks 5-8Escalation / maintenance
7.5mgWeeks 9-12Escalation
10mgWeeks 13-16Escalation / maintenance
12.5mgWeeks 17-20Escalation
15mgWeek 21+Maximum maintenance

Compare Contrave vs Mounjaro Australian Regulatory Status

Contrave

TGA StatusRegistered on ARTG for chronic weight management
PBS ListedNo PBS listing
Supply StatusNo supply issues
Key AdvantageOnly combination oral weight loss drug in AU; no injections needed
UK NameMarketed as Mysimba in the UK

Mounjaro

TGA StatusRegistered on ARTG for T2D, weight management, and OSA
PBS ListedNo PBS listing for any indication
Zepbound BrandUS/UK weight loss brand name not used in Australia
Supply StatusAvailability improving; no critical shortage reported
Oral VersionEli Lilly's oral GLP-1 (orforglipron) expected FDA decision mid-2026; not yet in AU

Full Contrave profile

View Contrave Details

Full Mounjaro profile

View Mounjaro Details

Compare Other Medications

Contrave vs Ozempic

~5-8% vs ~15% avg. weight loss

Contrave vs Wegovy

~5-8% vs ~15-17% avg. weight loss

Contrave vs Orlistat

~5-8% vs ~3-5% avg. weight loss

Contrave vs Saxenda

~5-8% vs ~8% avg. weight loss

Mounjaro vs Ozempic

~21% vs ~15% avg. weight loss

Wegovy vs Mounjaro

~15-17% vs ~21% avg. weight loss

View all weight loss medications

This website is for informational and research purposes only. We are not medical professionals and nothing on this page constitutes medical advice, diagnosis, or treatment. Always consult a qualified doctor or specialist before making any decisions about medication.

The weight loss medication landscape in Australia is changing rapidly. Information on this page may become outdated without notice. Data sourced from the TGA, FDA, MHRA, NICE, PBAC, Australian Prescriber, Obesity Evidence Hub, and clinical trial publications. Last reviewed March 2026.