Liraglutide (Saxenda) starts reducing appetite within the first week or two, but noticeable weight loss usually takes 1 to 3 months. You’ll spend the first 4 weeks gradually increasing your daily dose and reach the full 3 mg dose in week 5. The FDA label sets a clear checkpoint: if you haven’t lost at least 4% of your starting weight after 16 weeks, liraglutide likely isn’t working for you and should be stopped. In its main trial, people lost an average of 7.4% of their body weight over 56 weeks. Here’s what to expect, week by week.
Key takeaways
- Appetite changes often start in the first 1 to 2 weeks, before much weight comes off
- The dose rises every week for 4 weeks, reaching the full 3 mg daily dose in week 5
- Steady weight loss usually becomes noticeable between weeks 4 and 12
- At 16 weeks, the Saxenda label says to stop if you’ve lost less than 4% of your starting weight
- In the main trial, average weight loss at 56 weeks was 7.4%, vs 3.0% on placebo
- If you miss more than 3 days of doses, you need to restart at 0.6 mg
How liraglutide works
Liraglutide is a GLP-1 receptor agonist. It mimics a natural gut hormone that tells your brain you’re full, slows how quickly your stomach empties and helps regulate blood sugar. For weight management, it’s sold as Saxenda and as generic liraglutide.
Unlike weekly GLP-1 drugs, liraglutide is a daily injection. It reaches its highest level in the blood about 11 hours after each dose and has a half-life of about 13 hours. That’s why it needs to be taken every day to keep working, and why missed doses matter more than with weekly medications.
The liraglutide timeline: what to expect and when
| Time on liraglutide | What usually happens |
|---|---|
| Week 1 (0.6 mg) | Mild appetite changes for some people; little weight change |
| Weeks 2 to 4 (1.2 to 2.4 mg) | Fuller faster, fewer cravings; nausea is most common now |
| Week 5 onward (3 mg) | Full dose reached; appetite control becomes steadier |
| Weeks 4 to 12 | Weight loss becomes noticeable on the scale and in how clothes fit |
| Week 16 | Checkpoint: at least 4% weight loss means you’re likely to keep responding |
| Months 6 to 12 | Weight loss usually continues but slows, and many people reach a plateau within the first year |
Results vary from person to person, and progress is rarely a straight line. Weekly weigh-ins and a trend line give you a better picture than daily numbers.
The liraglutide dose schedule
The FDA label for Saxenda starts low and increases weekly to reduce digestive side effects:
| Week | Daily dose |
|---|---|
| 1 | 0.6 mg |
| 2 | 1.2 mg |
| 3 | 1.8 mg |
| 4 | 2.4 mg |
| 5 and beyond | 3 mg (maintenance) |
If side effects are hard to manage, your provider may keep you on a dose for an extra week before increasing. The general principle is the same as with other GLP-1 drugs. See how long to stay on each GLP-1 dose before increasing.
Explore your options: liraglutide · semaglutide · weight loss lab panel
The 16-week checkpoint
The Saxenda label includes a rule that many people don’t know about: evaluate your weight 16 weeks after starting, and stop liraglutide if you haven’t lost at least 4% of your starting weight.
For example, if you started at 220 pounds, you’d want to have lost about 9 pounds or more by week 16.
There’s good reason for this rule. Early response strongly predicts long-term results. In an analysis of the SCALE trials, 93.4% of people who hadn’t lost at least 5% by week 16 also didn’t reach 10% weight loss at one year. If liraglutide isn’t working by then, it’s usually better to switch to another treatment than to keep waiting.
How much weight can you lose on liraglutide?
In the main 56-week trial of Saxenda, 3,731 adults with obesity or overweight (without diabetes) took liraglutide 3 mg or placebo alongside diet and exercise:
| Result at 56 weeks | Liraglutide 3 mg | Placebo |
|---|---|---|
| Average weight loss | 7.4% | 3.0% |
| Lost at least 5% | 62.3% | 34.4% |
| Lost at least 10% | 33.9% | 15.4% |
In a separate trial of adults with type 2 diabetes, average weight loss was 6.0% on liraglutide 3 mg, compared with 2.0% on placebo. People with diabetes often lose a bit less weight on GLP-1 medications.
For a general sense of what’s realistic each month, see how much weight you can realistically lose in a month.
What affects how fast liraglutide works
Several factors can speed up or slow down your results:
- Reaching and staying on 3 mg. The full dose is where most of the effect comes from.
- Taking it every day. Because liraglutide clears in about a day, skipped doses quickly reduce its effect.
- What you eat. Protein, fiber and fewer liquid calories make the reduced appetite count.
- Physical activity. Regular walking plus two strength sessions a week support fat loss and protect muscle.
- Sleep and stress. Poor sleep and high stress raise hunger hormones.
- Other medications and conditions, such as insulin, some antidepressants, steroids or an underactive thyroid.
As weight comes off, your body also burns fewer calories, which naturally slows progress over time. We explain this in why you stop losing weight.
What to do if you miss a dose of liraglutide
According to the Saxenda label:
- If you miss one dose, skip it and take your next dose at the usual time the next day
- Don’t take an extra dose or increase your dose to make up for it
- If more than 3 days have passed since your last dose, restart at 0.6 mg and work back up through the weekly schedule
Restarting low after a break helps prevent strong nausea and vomiting. For step-by-step injection tips, see how to properly inject liraglutide.
Side effects in the first weeks
Digestive side effects are most common while the dose is increasing, then usually ease:
- Nausea, the most common
- Diarrhea or constipation
- Vomiting
- Reduced appetite and early fullness
- Mild injection site reactions
Smaller meals, slower eating and avoiding greasy food help. For why these effects happen and how to manage them, see why GLP-1 medications cause nausea. Contact your provider for vomiting that won’t stop, signs of dehydration, or severe stomach pain spreading to your back.
Liraglutide vs weekly GLP-1 medications
Liraglutide was one of the first GLP-1 drugs approved for weight loss, and newer weekly options generally produce more weight loss. In the STEP 8 head-to-head trial, people lost an average of 15.8% on weekly semaglutide compared with 6.4% on daily liraglutide over 68 weeks.
Liraglutide still has advantages for some people. Generic liraglutide has been available since August 2025 and may cost less, and it clears from the body quickly if side effects become a problem. For a full comparison, see semaglutide vs other GLP-1 medications. If you’re thinking about switching, read can you take semaglutide and liraglutide together first.
When to talk to your provider
Reach out if:
- You haven’t lost at least 4% of your starting weight by week 16
- Side effects are making it hard to eat, drink or keep up with daily life
- You’ve missed more than 3 days of doses and need to restart
- Your weight loss has stalled for several weeks on the full dose
- You’re interested in a weekly medication instead
The bottom line
Liraglutide starts working on appetite within the first week or two, but weight loss builds gradually, usually becoming noticeable between weeks 4 and 12. You reach the full 3 mg dose in week 5. The key milestone is week 16: if you’ve lost at least 4% of your starting weight, you’re likely to keep responding. If not, the label recommends stopping and considering another option. In trials, average weight loss was 7.4% at 56 weeks. Take it every day, follow the 3-day restart rule after missed doses, and pair it with protein, activity and good sleep for the best results.
Thinking about liraglutide or another GLP-1 option? Talk to a Heally provider about a weight loss prescription.
FAQ
How long does it take for liraglutide to start working?
Appetite changes often start within the first 1 to 2 weeks. Noticeable weight loss usually takes 1 to 3 months, after you’ve reached the full 3 mg dose in week 5.
How much weight can you lose on liraglutide in a month?
It varies, but early weight loss is usually modest while the dose is increasing. In the main trial, average weight loss was 7.4% over 56 weeks, which works out to well under 1% a month on average, with more lost in the earlier months.
What happens if liraglutide doesn’t work after 16 weeks?
The Saxenda label recommends stopping if you haven’t lost at least 4% of your starting weight after 16 weeks. Your provider can help you choose another option, such as a weekly GLP-1 medication.
When does liraglutide reach its full effect?
You reach the full 3 mg dose in week 5. Weight loss usually builds over the following months and slows later in the first year, as it does with most weight loss treatments.
What if I miss a dose of liraglutide?
Take your next dose at the usual time and don’t double up. If more than 3 days have passed since your last dose, restart at 0.6 mg and work back up through the weekly schedule.
Is liraglutide as effective as semaglutide?
No. In the STEP 8 trial, weekly semaglutide led to 15.8% average weight loss compared with 6.4% for daily liraglutide over 68 weeks. Liraglutide may still suit people who want a lower-cost generic option or a medication that clears quickly.
Sources
- US Food and Drug Administration. “SAXENDA (liraglutide) injection prescribing information,” revised October 2025. accessdata.fda.gov
- Pi-Sunyer X, et al. “A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management” (SCALE Obesity and Prediabetes). New England Journal of Medicine, 2015. pubmed.ncbi.nlm.nih.gov
- Davies MJ, et al. “Efficacy of Liraglutide for Weight Loss Among Patients With Type 2 Diabetes: The SCALE Diabetes Randomized Clinical Trial.” JAMA, 2015.
- Rubino DM, et al. “Effect of Weekly Subcutaneous Semaglutide vs Daily Liraglutide on Body Weight in Adults With Overweight or Obesity Without Diabetes: The STEP 8 Randomized Clinical Trial.” JAMA, 2022.
This article is for educational purposes only and is not a substitute for professional medical advice. Liraglutide is available by prescription only and carries an FDA boxed warning about the risk of thyroid C-cell tumors. Do not use it if you or a family member has had medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2.
