Library / Peptides / Weight Management / Liraglutide
Strong evidence · Grade A

Liraglutide

Liraglutide (Saxenda / Victoza)
Score
83 / 100
Half-life
~13 hours
Brand
Victoza · Saxenda
FDA
2010 · 2014
TL;DR
01
A once-daily GLP-1 receptor agonist, FDA-approved as Victoza (type 2 diabetes, 2010) and Saxenda (chronic weight management, 2014) — the first GLP-1 drug cleared for obesity.
02
In the pivotal SCALE Obesity trial, liraglutide 3.0 mg produced about 8% weight loss at 56 weeks (vs ~2.6% placebo); roughly two-thirds of participants lost at least 5%.
03
The LEADER cardiovascular outcomes trial showed a 13% reduction in major cardiovascular events in type 2 diabetes — a genuine, hard-endpoint benefit.
04
It has been clearly outperformed by the newer once-weekly agents: in a head-to-head trial, semaglutide 2.4 mg roughly doubled its weight loss.
05
Main side effects are gastrointestinal; it carries a boxed warning for thyroid C-cell tumors (a rodent finding) and is contraindicated with personal/family history of medullary thyroid cancer or MEN2.
Wt loss (SCALE Obesity, 3.0 mg)
−8.0%
NEJM 2015 · 56 wk
≥5% weight loss
63%
SCALE Obesity · 3.0 mg
CV events (LEADER)
−13%
MACE, HR 0.87 · NEJM 2016
vs semaglutide (STEP 8)
−6.4 vs −15.8%
JAMA 2022 · 68 wk
Dosing
Once daily
~13-h half-life, subcutaneous
Part 01 · How it works

Mechanism.

Liraglutide is a lab-modified copy of GLP-1, a gut hormone released after eating that tells the pancreas to release insulin and tells the brain you're full. Natural GLP-1 lasts only minutes; liraglutide is engineered to last about half a day, so a once-daily injection keeps appetite lower and blood sugar steadier. It's the same drug family as semaglutide and the GLP-1 half of tirzepatide — just an earlier, shorter-acting generation.

If your appetite has a thermostat, liraglutide nudges it down and holds it there for the day. It's the first-generation version of the dial that semaglutide later turned further.

GLP-1R agonism
Agonist at the GLP-1 receptor (class B GPCR) on pancreatic beta-cells and CNS satiety centers — glucose-dependent insulin secretion, delayed gastric emptying, appetite suppression.
Acylation / half-life
A fatty-acid (palmitoyl) chain promotes albumin binding, extending the half-life to ~13 h and enabling once-daily dosing.
Glucagon suppression
Reduces postprandial glucagon, lowering hepatic glucose output.
Cardiovascular effect
In LEADER, reduced major adverse cardiovascular events in type 2 diabetes — the first GLP-1 agonist to show this.
Part 02 · Dosing & administration

How it's taken.

Clinical · trial-validated

Values below describe how Liraglutide has been administered in human clinical trials and/or approved labeling. Provided for educational purposes only — this is not medical advice and not instructions for self-administration. Consult your healthcare provider before making any health decision.

Wk 1
0.6 mg
Starter dose to limit GI effects (Saxenda titration).
Wk 2
1.2 mg
Weekly step-up.
Wk 3
1.8 mg
Victoza (diabetes) tops out around here.
Wk 4
2.4 mg
Continued escalation toward the obesity dose.
TARGET
Wk 5+
3.0 mg
Saxenda maintenance dose for weight management.
·
Doses below are values from published trials and labeling, not instructions.
·
Victoza (type 2 diabetes) is dosed up to 1.8 mg; Saxenda (weight management) escalates to 3.0 mg — same molecule, different labeled maximum.
·
The weekly step-up exists specifically to reduce nausea; slowing it is common if GI symptoms are marked.
Need help with reconstitution?

Use the free peptide calculator for dilution, unit conversion, and injection volume.

Open calculator
Part 03 · Safety

Side effects, rare serious events, who shouldn't.

Common
Nausea
Most common; peaks early and usually attenuates (Saxenda labeling).
~39%
Diarrhea
Common, generally mild-to-moderate.
~21%
Constipation
Common; hydration and fiber typically manage it.
~19%
Vomiting
More likely during dose escalation.
~16%
Headache / injection-site reactions
Generally mild.
~14% / common
Serious · rare
Thyroid C-cell tumors (boxed warning)
Boxed warning based on rodent medullary thyroid tumors; contraindicated with personal/family history of MTC or MEN2. Human relevance unconfirmed.
Rodent finding
Acute pancreatitis
Discontinue for persistent severe abdominal pain radiating to the back.
<1%
Gallbladder disease
Cholelithiasis/cholecystitis, associated with rapid weight loss.
~2–3%
Hypoglycemia (in combination)
Risk rises mainly when combined with insulin or a sulfonylurea.
Dose-dependent
Absolute · do not use
×
Personal or family history of medullary thyroid carcinoma (FDA boxed warning)
×
Multiple endocrine neoplasia syndrome type 2 (MEN2) (FDA boxed warning)
×
Known hypersensitivity to liraglutide or any product component
×
History of pancreatitis (use with caution)
×
Pregnancy or breastfeeding
×
Concurrent use of another GLP-1 receptor agonist
Relative · discuss first
!
Personal or family history of medullary thyroid carcinoma or MEN2 — boxed contraindication, not merely relative
!
History of pancreatitis — discuss with GI / endocrinology first
!
Pregnancy or breastfeeding — discontinue if pregnancy is planned or occurs
!
Severe gastroparesis or active GI disease — delayed gastric emptying may worsen symptoms
!
Concurrent insulin or sulfonylurea — monitor for hypoglycemia
Interactions
Insulin
Per FDA label: increased risk of hypoglycemia; consider reducing insulin dose when starting liraglutide
Major
Sulfonylureas
Per FDA label: increased risk of hypoglycemia; consider sulfonylurea dose reduction
Major
Oral medications (general)
Per FDA label: liraglutide slows gastric emptying and may affect the rate of absorption of co-administered oral drugs; monitor where timing matters
Moderate
Other GLP-1 receptor agonists
Overlapping mechanism with no added benefit and increased GI and hypoglycemia risk; not recommended together
Major
Labs to monitor
HbA1c
Baseline and every 3 months
Primary glycemic marker when used for diabetes
Fasting Glucose
Baseline and periodically
Track glycemic response and hypoglycemia risk
Lipase & Amylase
Baseline and if symptomatic
Pancreatitis screening (GLP-1 class concern)
Comprehensive Metabolic Panel
Baseline and every 3-6 months
Kidney function and gallbladder/liver screening
Thyroid Panel (TSH)
Baseline and as clinically indicated
GLP-1 class thyroid C-cell concern
Part 04 · Evidence

How strong is the evidence?

83
Grade A
Grade A. Multiple phase 3 trials across diabetes and obesity, a positive cardiovascular outcomes trial (LEADER), and more than a decade of real-world use. The main caveat is not safety but positioning: newer once-weekly agents deliver substantially more weight loss.
Mechanistic plausibility
Well-mapped GLP-1 biology; first-in-class validation for the obesity indication.
90
Human evidence
SCALE program (obesity + diabetes), LEADER CVOT, and extensive independent post-marketing data.
90
Safety & tolerability
GI-dominant and mostly transient; boxed thyroid C-cell warning (rodent) and a modest gallbladder-event signal; long track record.
78
Durability
Weight is regained after discontinuation; daily dosing adds an adherence burden vs weekly agents.
72
Independence
Pivotal trials Novo Nordisk-sponsored, but corroborated by large independent reviews and meta-analyses.
70
Part 05 · Research log

Every study we cite.

We list each study with its methodology, funding source, and our quality grade. Flagged studies aren't dismissed — they're tagged so you can weigh them.

01
2015
New England Journal of Medicine Industry funded
SCALE Obesity and Prediabetes — liraglutide 3.0 mg for weight management
Mean weight loss −8.0% (−8.4 kg) vs −2.6% placebo; 63% achieved ≥5% and 33% achieved ≥10% weight loss.
RCT, 56 wk, placebo-controlled (adults without diabetes) · n = 3,731 · Funded by Novo Nordisk; lifestyle co-intervention in all arms.
PMID 26132939 ↗
High
02
2015
JAMA Industry funded
SCALE Diabetes — liraglutide for weight loss in type 2 diabetes
Weight loss −6.0% (3.0 mg) vs −2.0% placebo in adults with type 2 diabetes; improved glycemic measures.
RCT, 56 wk, placebo-controlled · n = 846 · Funded by Novo Nordisk; weight loss smaller in diabetes than in the non-diabetic SCALE cohort, consistent with the class.
PMID 26284720 ↗
High
03
2016
New England Journal of Medicine Industry funded
LEADER — cardiovascular outcomes with liraglutide in type 2 diabetes
13% relative reduction in major adverse cardiovascular events (HR 0.87) and lower cardiovascular and all-cause mortality — a hard-endpoint benefit.
RCT CVOT, median 3.8 yr, placebo-controlled · n = 9,340 · Funded by Novo Nordisk and NIH; high-cardiovascular-risk diabetic population, so the CV result may not generalize to lower-risk obesity patients.
PMID 27295427 ↗
High
04
2022
JAMA Industry funded
STEP 8 — semaglutide 2.4 mg weekly vs liraglutide 3.0 mg daily
Liraglutide −6.4% vs semaglutide −15.8% (difference −9.4 pp, p<0.001); liraglutide had higher treatment discontinuation (27.6% vs 13.5%).
Phase 3b RCT, 68 wk, active-controlled head-to-head · n = 338 · Funded by Novo Nordisk (maker of both drugs); active-comparison was open-label. Directly places liraglutide below the current weekly standard.
PMID 35015037 ↗
High
05
2025
Nature Medicine Flagged
Network meta-analysis of pharmacological obesity treatments
Liraglutide's weight-loss effect ranks below the once-weekly agents (semaglutide, tirzepatide), consistent with the head-to-head data.
Systematic review and network meta-analysis of 56 RCTs · Independent synthesis; network (mostly indirect) comparisons carry more uncertainty than head-to-head trials.
PMID 41039116 ↗
High
Evidence against

What didn't work, and where the evidence is thin.

Every publication is incentivized to tell you a peptide works. We catalogue the null results, failed trials, and mechanism limits we found in the same literature — so you can weigh them against the upside, with your provider.

01
Beaten head-to-head by semaglutide
Lost head-to-head
JAMA (STEP 8) · 2022
In the only direct phase 3 comparison, once-weekly semaglutide 2.4 mg produced −15.8% weight loss vs −6.4% with once-daily liraglutide 3.0 mg — roughly double — and liraglutide had more than twice the discontinuation rate (27.6% vs 13.5%).
What this means: For weight loss, liraglutide is now a second-line choice within its own class. Its case rests on cost, a longer safety record, and daily-dose flexibility rather than efficacy.
PMID 35015037 ↗
02
Lower efficacy ceiling and daily-dose burden vs weekly agents
Mechanism limit
Nature Medicine (network meta-analysis) · 2025
Across 56 RCTs, liraglutide consistently ranks below the once-weekly incretin agents for weight loss, and its daily injection schedule adds an adherence burden the weekly drugs avoid.
What this means: Even setting the head-to-head aside, the broader evidence base places liraglutide's effect size and convenience behind the current front-line options.
PMID 41039116 ↗
Part 06 · Cost & access

Where it's available, at what price.

United States
FDA-approved
Rx via PCP / endocrinology / obesity medicine. Victoza (T2D) and Saxenda (obesity) are separate products; a generic liraglutide is now available. Weight-indication insurance coverage varies.
~$1,300/mo cash for Saxenda; less with coverage or generics
European Union
Approved
Approved as Victoza and Saxenda; prescription-only.
Varies by country and reimbursement
United Kingdom
Approved
Saxenda available through specialist weight-management services and privately; Victoza for diabetes.
NHS access restricted by criteria; private ~£200+/mo
Canada
Approved
Approved as Victoza and Saxenda; prescription-only.
Varies by province and private coverage
The Peptide Column takes no affiliate commission from any source. Liraglutide is a prescription-only medicine in every approved jurisdiction; we link only to clinician-directed access, never to sellers.
Part 07 · Your appointment

Questions to bring.

01
Am I a candidate for liraglutide for diabetes (Victoza) or weight management (Saxenda), and how does it compare to once-weekly options?
02
What daily dose-escalation schedule should I follow, and how are nausea and other GI side effects managed?
03
What are my risks for pancreatitis, gallbladder disease, and the thyroid C-cell concern noted in the boxed warning?
04
How long is treatment expected to continue, and what happens to weight or blood sugar if I stop?
References

Every citation, numbered.

Citation list. For our editorial read of each study — including bias flags and quality grades — see the Research log above.

  1. 01.
    SCALE Obesity and Prediabetes — liraglutide 3.0 mg for weight management · New England Journal of Medicine, 2015 · PMID 26132939 ↗
  2. 02.
    SCALE Diabetes — liraglutide for weight loss in type 2 diabetes · JAMA, 2015 · PMID 26284720 ↗
  3. 03.
    LEADER — cardiovascular outcomes with liraglutide in type 2 diabetes · New England Journal of Medicine, 2016 · PMID 27295427 ↗
  4. 04.
    STEP 8 — semaglutide 2.4 mg weekly vs liraglutide 3.0 mg daily · JAMA, 2022 · PMID 35015037 ↗
  5. 05.
    Network meta-analysis of pharmacological obesity treatments · Nature Medicine, 2025 · PMID 41039116 ↗
  6. 06.
    FDA prescribing information. Official US labels — Victoza and Saxenda · Source ↗
  7. 07.
    ClinicalTrials.gov. STEP 8 head-to-head (NCT04074161) · Source ↗