Week by week — from your first dose through the first year
Last reviewed: September 2026·Based on 1 clinical trial
Your dose schedule
1
Step-up dosesWeeks 1–4
The dose is titrated upward across the first four weeks, taken as extended-release tablets twice daily.
2
32 mg / 360 mg per dayWeeks 5+
The full daily dose used in the COR trials.
Maintenance
Key insight
The first four weeks are a step-up period, and they are also when nausea is most likely — it was the single most common reason people stopped in the trials.
Starting Contrave — what to expect
Twice a day, not once
Contrave is an extended-release tablet taken twice daily. That is a different habit from the once-daily and weekly options, and worth planning around from day one.
Take it with food
Nausea was reported by about 1 in 3 trial participants and was the most common reason people stopped. Taking the tablets with food, especially the evening dose, is the tip long-term users share most often.
Tell every prescriber you take it
The naltrexone component blocks opioids, including codeine-containing cough medicines and tramadol. Chronic opioid use is a contraindication on the label.
Get your blood pressure checked
The label warns about increases in blood pressure and heart rate, and uncontrolled high blood pressure is a contraindication. Monitoring is part of taking this drug.
What most people experience
The dose steps up over four weeks. Appetite and craving changes are typically noticed within 4 to 8 weeks, so the first month is mostly about getting onto the full dose and through the early nausea.
Your journey — what typically happens month by month
Based on COR-I trial data (56 weeks) and patient-reported outcomes. Average weight loss was 6.1% at 56 weeks. Individual experiences vary significantly.
Weeks 1–4
The four-week step-up
The dose is titrated up to 32/360 mg per day. Nausea is the most likely side effect in this window — about 1 in 3 trial participants reported it, against about 1 in 15 on placebo.
What to watch: Whether nausea is manageable with food. It was the reason 6.3% of trial participants stopped, so it is worth raising early rather than pushing through silently.
Weeks 4–8
Appetite and craving changes
Appetite and craving changes are typically noticed within 4 to 8 weeks. Contrave acts on brain reward and craving pathways rather than only on fullness, which is why cravings are often the first thing people notice shifting.
What to watch: Whether the pull toward particular foods has changed. That is the effect this drug is designed to produce.
Weeks 16–24
Significant weight loss
Significant weight loss is typically seen by 16 to 24 weeks. COR-I measured its headline 6.1% average at 56 weeks, so the numbers at this stage are smaller.
What to watch: The trend across four-week windows. Also worth knowing: in COR-BMOD, pairing the drug with structured lifestyle coaching produced 9.3% average loss against 5.1% for coaching alone.
Beyond 56 weeks
Staying on, and stopping properly
In COR-I, average weight loss at 56 weeks was 6.1% against 1.3% on placebo, with 48% of participants losing at least 5% of their weight. Weight regain after stopping is expected.
What to watch: Contrave has to be tapered rather than stopped abruptly, because stopping suddenly can cause withdrawal from the bupropion component.
Key insight
Contrave starts with twice-daily tablets and a four-week dose step-up. In the COR-I trial, 24% of participants on Contrave stopped because of side effects, compared with 12% on placebo. Getting through the early nausea with food is most of the battle.
Tips for starting — what actually helps
Some tips apply to everyone on weight loss medication. Others are specific to Contrave. Both matter most in the first 8 weeks.
Contrave-specific
Always with food
Nausea was the single most common reason people stopped in the trials. Taking the tablets with food — especially the evening dose — is the most repeated practical tip from long-term users.
Important
No opioids, at all
The naltrexone component blocks opioids and can trigger withdrawal. That includes codeine cough syrup and tramadol. Tell every prescriber, dentist and pharmacist.
Important
Watch your mood, and let someone else watch too
The boxed warning is about suicidal thoughts and behaviour. The label says to watch closely for new or worsening depression, especially in the first months. Tell someone close to you what to look for.
Contrave-specific
Blood pressure checks
The label warns about increases in blood pressure and heart rate. Regular checks are part of taking this drug rather than an optional extra.
Important
Do not stop abruptly
Stopping suddenly can cause withdrawal from the bupropion component. Any stop should be tapered with your prescriber.
General
Protein at every meal
When appetite and cravings drop, what you eat has to work harder. Protein protects muscle during weight loss.
General
Pair it with structure if you can
In COR-BMOD, the drug combined with intensive behaviour therapy produced 9.3% average weight loss against 5.1% for the therapy alone. The combination did more than either part.
General
Weigh weekly, not daily
Day-to-day weight moves by several pounds on water and food alone. Track the trend across weeks.
What people actually say about starting
Personal experiences from public online communities — not medical advice.
“Nausea is worst in the first 2–4 weeks. Taking it with food — especially for the evening dose — helps significantly.”
r/Contrave
“If you use any opioid medications (including codeine cough syrup or tramadol), you cannot take this drug — the naltrexone will block them and can cause withdrawal.”
r/Contrave
Bottom line
→Weeks 1–4: the dose steps up to 32/360 mg per day. Nausea is most likely here — take it with food.
→Weeks 4–8: appetite and craving changes are typically noticed in this window.
→Weeks 16–24: significant weight loss is typically seen by this point.
→At 56 weeks: COR-I found 6.1% average loss; COR-BMOD found 9.3% when the drug was paired with structured coaching.
→One rule that is not optional: never stop abruptly — this one has to be tapered with your prescriber.
Common questions
Appetite and craving changes are typically noticed within 4 to 8 weeks, with significant weight loss by 16 to 24 weeks. The first four weeks are taken up stepping the dose up to 32/360 mg per day.
Mostly like getting onto the dose. Nausea was reported by about 1 in 3 trial participants and was the most common reason people stopped, so taking the tablets with food matters more here than with most medications.
It acts on brain reward and craving pathways rather than only on fullness. Bupropion activates appetite-suppressing nerve cells in the hypothalamus, and naltrexone blocks the feedback signal that would otherwise switch that effect off.
In COR-BMOD, the drug combined with intensive behaviour therapy produced 9.3% average weight loss against 5.1% for the same therapy plus placebo. Both figures come from the same 56-week trial.
Opioids are the problem: the naltrexone component blocks them, and chronic opioid use or acute opioid withdrawal is a contraindication on the label. That includes codeine-containing cough medicines and tramadol. Check anything else with your pharmacist.
No. Contrave has to be tapered rather than stopped abruptly, because stopping suddenly can cause withdrawal from the bupropion component. Plan any stop with your prescriber.
Written and maintained by one person · Built with agentic AI tools · Every number checked against the cited trial · Not medical advice
Built with agentic AI tools and not a substitute for medical advice
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