Side-by-side · Research reference
LiraglutidevsSemaglutide
Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.
AFDA-ApprovedVerified14/45 cited
BFDA-ApprovedVerified15/53 cited
Liraglutide
Daily GLP-1 RA · FDA-Approved
SQ · Abdomen / thigh / arm · Once daily
Semaglutide
GLP-1 RA · FDA-Approved
SQ · Abdomen / thigh / arm · Once weekly
01Mechanism of Action
Parameter
Liraglutide
Semaglutide
Primary target
GLP-1 receptor (GLP-1R)SAXENDA (liraglutide) injectio 2014
GLP-1 receptor (GLP-1R)WEGOVY (semaglutide) injection 2021
Pathway
GLP-1R agonism → ↑glucose-dependent insulin, ↓glucagon, ↓gastric emptying, ↓appetiteSAXENDA (liraglutide) injectio 2014Marso 2016
GLP-1R agonism → ↑glucose-dependent insulin secretion, ↓glucagon, ↓gastric emptying, ↓appetite via hypothalamic centresWilding 2021
Downstream effect
Glycemic improvement, modest body-weight reduction, cardiovascular event reduction in high-risk T2DMarso 2016
Improved glycemic control, reduced caloric intake, body-weight reduction, cardiovascular risk reductionWilding 2021
Feedback intact?
Glucose-dependent insulin release preserves physiological feedback
Glucose-dependent insulin release preserves physiological feedback
Origin
Modified GLP-1(7-37) with Lys26 substitution (Arg34) and C-16 palmitoyl-glutamate acylation for albumin bindingSAXENDA (liraglutide) injectio 2014
Modified GLP-1(7-37) with two amino-acid substitutions and C-18 fatty-acid acylation for albumin binding and 168-h half-lifeWEGOVY (semaglutide) injection 2021
Antibody development
—
—
02Dosage Protocols
Parameter
Liraglutide
Semaglutide
Standard dose (weight, Saxenda)
3.0 mg / day (after 5-week titration)SAXENDA (liraglutide) injectio 2014
—
Frequency
Once daily, same time each day
Once weekly, same day each week
Titration schedule
0.6 → 1.2 → 1.8 → 2.4 → 3.0 mg over 5 weeks
Mitigates GI side effects.
0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg over 16 weeks
Mitigates GI side effects.
Evidence basis
FDA-approved · Phase 3 RCTs (LEADER, SCALE)Marso 2016SAXENDA (liraglutide) injectio 2014
FDA-approved · Phase 3 RCTsWilding 2021WEGOVY (semaglutide) injection 2021
Duration
Indefinite for chronic indication
Indefinite for chronic indication
Discontinuation results in weight regain.
Reconstitution
Pre-filled commercial pen (no reconstitution)
Pre-mixed pen device (commercial). Research lyophilised vial: bacteriostatic water per label.
Timing
Any time of day; consistent
Any time of day, with or without food
Half-life
~7 days (168 h)WEGOVY (semaglutide) injection 2021
Standard dose (weight, Wegovy)
—
2.4 mg / week (after 16-wk titration)WEGOVY (semaglutide) injection 2021Wilding 2021
04Side Effects & Safety
Parameter
Liraglutide
Semaglutide
GI symptoms
Nausea, vomiting, diarrhea (very common during titration)SAXENDA (liraglutide) injectio 2014
Nausea, vomiting, diarrhea, constipation (very common)Wilding 2021
Pancreatitis risk
Rare; discontinue if suspected
Rare; discontinue if suspectedWEGOVY (semaglutide) injection 2021
Thyroid C-cell tumours
Boxed warning — contraindicated in MEN2 / MTC historySAXENDA (liraglutide) injectio 2014
Boxed warning — contraindicated in MEN2 / personal or family MTC historyWEGOVY (semaglutide) injection 2021
Hypoglycemia
Low risk as monotherapy; elevated with sulfonylureas / insulin
Low risk as monotherapy; elevated when combined with sulfonylureas / insulin
Heart rate
Modest ↑ resting HR (~2-3 bpm)
Modest ↑ resting HR (~2-4 bpm)
Injection site reaction
—
Mild erythema, pruritus
Gallbladder events
—
Increased cholelithiasis
Absolute Contraindications
Liraglutide
- ·MTC personal or family history; MEN2
- ·Pregnancy / breastfeeding
- ·Hypersensitivity to liraglutide
Semaglutide
- ·Personal or family history of medullary thyroid carcinoma
- ·Multiple endocrine neoplasia syndrome type 2
- ·Pregnancy / breastfeeding
- ·Hypersensitivity to semaglutide
Relative Contraindications
Liraglutide
- ·Severe gastroparesis
- ·History of pancreatitis
- ·Severe gastrointestinal disease
Semaglutide
- ·Severe gastroparesis
- ·History of pancreatitis
- ·Diabetic retinopathy (may worsen with rapid glycemic improvement)
05Administration Protocol
Parameter
Liraglutide
Semaglutide
1. Reconstitution / device
Commercial pre-filled pen, no reconstitution required.
Commercial: pre-filled pen, no reconstitution. Research vial: per-label or bacteriostatic water.
2. Injection site
SQ — abdomen, thigh, or upper arm. Rotate sites.
SQ — abdomen, thigh, or upper arm. Rotate sites weekly to avoid lipohypertrophy.
3. Timing
Once daily, same time each day. Take with or without food.
Once weekly, same day. Day can be changed if ≥2 days separate doses.
4. Storage
Refrigerate 2–8 °C unopened; room temp ≤30 °C up to 30 days after first use.
Pen: refrigerate 2–8 °C unopened; room temp ≤30 °C up to 56 days after first use.
5. Needle
Pen-supplied 32G needle.
Pen-supplied 31–34G needle. Research vial: 27–31G insulin syringe.
06Stack Synergy
Liraglutide
— no documented stacks
Semaglutide
+ Tirzepatide
WeakCombining two GLP-1 RA-class drugs is not clinically validated and risks additive GI toxicity. Tirzepatide's GIP component already provides complementary mechanism vs pure GLP-1; stacking with semaglutide adds receptor saturation but no synergy. NOT recommended.
- Note
- Stack not recommended — choose one GLP-1 RA
- Primary benefit
- (none — additive toxicity, no synergy)