Skip to the catalogue
halfrx
Contrave (naltrexone/bupropion)

How long does Contrave take to work?

Earliest week the maintenance dose is reachable
Week 4

About a month of dose escalation across 4 steps before the dose anyone stays on — quoted from the label, not estimated.

Last updated 2025-11-17the version of the FDA label this schedule comes from

How long does it take for Contrave to work?

Contrave reaches its maintenance dose no earlier than week 4, because the FDA label steps the dose up on a schedule rather than starting at the dose that does the work. That is about a month of titration before the dose anyone stays on, across 4 steps, and it is the reason an advertised first-month price says so little. The figure people are usually asking about is the 6.4% mean weight loss its label cites, and that came from COR-II, phase 3: 6.4% mean weight loss at week 56 against 1.2% on placebo;… Appetite changes are usually reported within the first weeks, but the trial figure is measured over its full length rather than at any earlier point — the two are different claims and are often quoted as one. Every week of that schedule is billed: $99 a month at maintenance on this site, verified against the seller's own page.

The schedule, week by week — and what each week costs

Doses and intervals are quoted from FDA prescribing information for Contrave (naltrexone/bupropion). Prices are the published figure for that dose where the manufacturer prices per step; where it charges one price throughout, the column says so.

WhenDoseA month at this stepWhat the label notes
Week 11 tablet in the morning$99 — one price throughout
Week 21 morning, 1 evening$99 — one price throughout
Week 32 morning, 1 evening$99 — one price throughout
Week 4 and on2 morning, 2 evening$99 — one price throughoutThe full dose: 32 mg naltrexone and 360 mg bupropion a day.

What “working” is being measured

The number quoted everywhere for Contrave is 6.4% mean weight loss, and it comes from COR-II, phase 3: 6.4% mean weight loss at week 56 against 1.2% on placebo; 50.5% of treated participants lost at least 5% of body weight against 17.1% on placebo That figure is the endpoint of a trial, not a milestone you pass on a particular week — and it is a mean, so half the participants were below it.

Appetite change is the thing most people notice first and it is commonly reported in the early weeks — at doses the label itself calls initiation rather than treatment. Conflating that with the trial figure is how “it works in a week” gets written.

The reactions the label lists in at least 5% of patients — nausea, constipation, headache, vomiting, dizziness — cluster just after a step up rather than at a steady dose. The full label list →

Contrave timeline, answered

How long before Contrave starts working?
Two different things get called "working". Appetite changes are commonly reported within the first weeks, at doses the label describes as initiation rather than treatment. The weight-loss figure people quote is measured over a full trial at the maintenance dose, which this label does not reach before week 4. A page that answers with one number is answering only one of the two questions.
Can the schedule be moved faster?
That is a prescriber's decision and this page does not advise on it. What the label says is the escalation interval it was studied at; going faster is off-label territory and going slower is common where side effects are hard. The reactions the label lists — nausea, constipation, headache, vomiting — are typically worst just after a step up.
Do I pay for the titration months?
Yes, every one of them. Contrave is $99 a month at maintenance on this site. The months before maintenance are not free trial months; they are billed at the price for that dose.

The schedule is quoted from FDA prescribing information for Contrave (naltrexone/bupropion), read directly. This page reports what the label says and does not recommend a dose or a schedule; that is a conversation with a prescriber. Information only, not medical advice.