There is no set maximum duration for taking Contrave. The FDA label does not specify an end date, and current obesity treatment guidelines treat the condition as a chronic disease that may require ongoing medication. That said, there is a critical checkpoint: if you haven’t lost at least 5% of your starting body weight by 16 weeks, the recommendation is to stop, because meaningful results are unlikely with continued use.
The 16-Week Checkpoint
Contrave uses a gradual dose increase over the first three weeks, reaching the full maintenance dose at the start of week four. From that point, you get 12 weeks at the full dose before the first real evaluation. That puts the checkpoint at roughly 16 weeks from when you started the medication.
The FDA label is clear on this: if you haven’t lost at least 5% of your baseline body weight by that point, discontinue the medication. This isn’t an arbitrary cutoff. Clinical data shows that people who don’t respond by 16 weeks rarely catch up later. The 5% threshold is the minimum considered “clinically meaningful,” meaning it’s enough to start improving markers like blood sugar, blood pressure, and cholesterol.
What the Clinical Trials Show
The largest clinical trial for Contrave ran for 56 weeks. Participants taking the approved dose lost an average of 6.1% of their body weight, compared to 1.3% in the placebo group. Nearly half of people on Contrave (48%) lost 5% or more of their body weight, versus 16% on placebo. So the medication clearly works for a meaningful portion of users, but it’s not universal.
Nausea was the most common side effect, affecting about 30% of participants. Headache, constipation, dizziness, vomiting, and dry mouth also occurred more frequently than with placebo. More people in the Contrave groups dropped out due to side effects than in the placebo group. One reassuring finding: the medication was not associated with increased depression or suicidal thoughts compared to placebo. Blood pressure showed a brief, small increase early on (about 1.5 mm Hg) followed by a slight decrease below baseline.
Why Long-Term Use Is Common
Obesity is increasingly recognized as a chronic condition, not a temporary problem solved by a short course of medication. The American Association of Clinical Endocrinology classifies it as a “neurohormonal metabolic disease,” noting that the body actively defends its fat stores. When you lose weight, your body adjusts its hunger signals and metabolism to push you back toward your previous weight. Medications like Contrave work by acting on the brain pathways that drive this response.
This is why many prescribers keep patients on Contrave indefinitely, as long as it continues working and side effects remain tolerable. Stopping the medication removes the support those brain pathways were getting, and weight regain typically follows.
What Happens When You Stop
A 2025 systematic review published in The BMJ examined weight regain after stopping weight management medications, including Contrave’s combination of naltrexone and bupropion. The findings were striking: people regained an average of 0.4 kg (just under a pound) per month after stopping. Within the first year off medication, the average weight regain was about 4.8 kg (roughly 10.5 pounds). By approximately 1.7 years after stopping, most people had returned to their pre-treatment weight entirely.
It wasn’t just weight that bounced back. Fasting blood sugar, blood pressure, cholesterol, and triglycerides were all projected to return to baseline levels within about a year of stopping medication. This pattern held across different weight loss drugs, not just Contrave, reinforcing the idea that for many people, sustained medication use is what sustains the results.
Monitoring During Extended Use
If you stay on Contrave long term, expect regular blood pressure and heart rate checks. The FDA label calls for monitoring at regular intervals, particularly if you had high blood pressure before starting. This is standard for any ongoing medication, but it matters here because one of Contrave’s ingredients (bupropion) can affect blood pressure in some people.
People with liver or kidney problems may need dose adjustments, so those conditions should be discussed with a prescriber before starting and monitored over time. There’s no evidence that long-term use causes progressive organ damage in people with normal liver and kidney function, but routine lab work helps catch any issues early.
Practical Timeline for Most Users
Here’s what the typical Contrave timeline looks like in practice:
- Weeks 1 through 3: Gradual dose increase. Side effects like nausea are most common during this period.
- Week 4: Full maintenance dose reached.
- Week 16: First major evaluation. If you haven’t lost 5% of your starting weight, the medication should be stopped.
- Beyond week 16: If it’s working, you continue with periodic check-ins. There is no predetermined stopping point.
Some people stay on Contrave for years. Others use it for a defined period while building diet and exercise habits, then taper off with the understanding that some weight regain is likely. The right duration depends on your response, your side effect profile, and how your weight and health markers trend over time.