Liraglutide
Lira · Victoza · Saxenda · NN2211
Daily first-generation GLP-1 agonist; weaker and more injection-heavy than the weekly analogues.
Typical dose
1.8 mg
Once daily
Range
0.6–3
mg
Half-life
13 h
see Dosing
Evidence
Human trials
Subcutaneous
What it is
Liraglutide is a GLP-1 receptor agonist and the direct predecessor to semaglutide. It is human GLP-1 with a single Arg substitution and a C16 palmitic acid chain attached through a glutamate spacer, which slows absorption and lets it bind albumin. That gets the half-life to about 13 hours, enough for daily but not weekly dosing.
It is approved as Victoza for type 2 diabetes at up to 1.8 mg daily and as Saxenda for weight management at up to 3.0 mg daily. The SCALE trial produced about 8% mean body weight loss over 56 weeks at 3.0 mg, against 2.6% on placebo.
It has largely been displaced by semaglutide and tirzepatide, which lose roughly twice as much weight on one injection a week instead of seven. Its main practical advantage now is the short half-life: if you react badly, it clears in two to three days rather than five weeks.
Generic liraglutide has entered several markets since patent expiry, so it is often cheaper than the weekly compounds and available as a pharmaceutical pen rather than a grey-market vial.
How it works
Liraglutide activates GLP-1 receptors in the hypothalamus and brainstem to increase satiety and reduce food intake, slows gastric emptying so meals feel larger and last longer, and in the pancreas increases glucose-dependent insulin secretion while suppressing glucagon.
The pharmacokinetics are the whole difference from semaglutide. The single C16 fatty acid causes the peptide to self-associate at the injection site and bind albumin in circulation, but far less avidly than semaglutide's C18 diacid. The result is a 13-hour half-life with a genuine peak and trough each day, rather than the flat weekly exposure of the newer analogues, which is part of why appetite suppression is less complete and nausea more clustered after each injection.
Dosing
Titration is weekly, not monthly as with the long-acting analogues: 0.6 mg increments each week up to 3.0 mg for weight management or 1.8 mg for glycaemic control.
Standard titration
| Step | Dose | Note |
|---|---|---|
| Week 1 | 0.6 mg | Tolerance dose only; not therapeutic |
| Week 2 | 1.2 mg | Appetite effect becomes noticeable |
| Week 3 | 1.8 mg | Maximum Victoza dose; a common stopping point |
| Week 4 | 2.4 mg | Weight-management territory |
| Week 5 onward | 3 mg | Saxenda maximum; hold here if tolerated |
Reconstitution calculator
Pre-loaded with Liraglutide’s vial size, water volume and typical dose. Change anything.
Typical: 1.8 mg · range 0.6–3
Draw to
36 u
0.36 mL · 1.8 mg
Concentration
5 mg/mL
50 mcg per unit
Doses per vial
2.8
Vial lasts
2.8 days
Draw to 36 units on the barrel.
Once mixed
Refrigerate at 2-8C and use within about 4 weeks; pharmaceutical pens in use are rated for 30 days at up to 30C.
A 5 mg vial with 1 mL bacteriostatic water gives 5 mg/mL, so 0.6 mg is 12 units on a U-100 insulin syringe and 3.0 mg is 60 units. Because it is dosed daily, a 5 mg vial only lasts about three days at 1.8 mg, so 10 mg vials are the more practical buy. Most pharmaceutical liraglutide is a prefilled 3 mL pen at 6 mg/mL and needs no reconstitution.
Storage
Before mixing
Refrigerated at 2-8C the sealed powder is stable for years; keep it dark and dry and tolerate ambient shipping only briefly.
After mixing
Refrigerate at 2-8C and use within about 4 weeks; pharmaceutical pens in use are rated for 30 days at up to 30C.
Reported benefits
- ▪About 8% mean body weight loss over 56 weeks at 3.0 mg in trial conditions
- ▪Reduced major cardiovascular events in type 2 diabetics in the LEADER trial
- ▪Short half-life means side effects and any bad reaction clear within a few days
- ▪Effective glycaemic control with low standalone hypoglycaemia risk
- ▪Cheaper than the weekly analogues in markets with generics
- ▪Fast weekly titration reaches a working dose in about a month
Side effects
- ▪Nausea and vomiting, typically clustered in the hours after each injection rather than spread across the week
- ▪Diarrhoea or constipation, and reflux from delayed gastric emptying
- ▪Injection site nodules, more common than with weekly compounds simply from seven times the injections
- ▪Lean mass loss in a deficit if protein and training volume are not held
- ▪Gallstones, linked to the rate of weight loss
- ▪Acute pancreatitis, rare but documented
- ▪Headache and fatigue during titration
- ▪Markedly delayed gastric emptying — the stomach can still hold solid food many hours after a meal, so any surgery, endoscopy or procedural sedation needs the drug held beforehand and the anaesthetist told, because of the aspiration risk from retained gastric contents.
Do not use if
- ▪Personal or family history of medullary thyroid carcinoma or MEN2 syndrome
- ▪History of pancreatitis
- ▪Gastroparesis or significant gastric motility disorder
- ▪Pregnancy or trying to conceive
- ▪Concurrent use of another GLP-1 receptor agonist
Evidence level — Human trials
Controlled human clinical data exists.
FDA- and EMA-approved as a prescription drug (Victoza, Saxenda), now with generics in several markets; loose vials sold outside that channel are unlicensed research-chemical supply.
Commonly run with
BPC-157
Gastric-juice-derived pentadecapeptide studied for tendon, ligament and gut healing.
250 mcg · 1x daily (some split into 2x daily during an acute injury)
Tesamorelin
The only FDA-approved GHRH analogue, proven to shrink visceral abdominal fat.
2 mg · once daily
5-Amino-1MQ
Oral NNMT inhibitor aimed at fat-cell metabolism and NAD+ salvage. Mouse data only.
100 mg · once daily
Liraglutide FAQ
Why would anyone use liraglutide over semaglutide?+
Three reasons: cost, since generics exist; availability of a real pharmaceutical pen rather than a grey-market vial; and the 13-hour half-life. If you tolerate GLP-1s badly, a bad reaction on liraglutide is gone in two or three days, whereas semaglutide takes about five weeks to clear.
How much weight loss should I expect?+
Roughly 8% of body weight over a year at 3.0 mg in trial conditions, against about 15% for semaglutide at 2.4 mg and 21% for tirzepatide at 15 mg. It works, but it is clearly the weakest of the four incretins in this group.
Can I switch from liraglutide to semaglutide?+
Yes, and it is a common move. Stop liraglutide and start semaglutide at the standard 0.25 mg starting dose on the next scheduled day; there is no need for a washout given liraglutide's short half-life. Do not try to convert your daily dose into a weekly equivalent.
Does the daily injection cause problems?+
Mainly adherence and injection site nodules. Seven subcutaneous injections a week in the same few sites builds up lumps, so rotate abdomen, thigh and upper arm systematically. The nausea also spikes after each dose rather than staying level, which some people find harder to live with than a weekly compound.
Will I keep muscle on it?+
The same rules apply as with any GLP-1: lean mass loss tracks the size and speed of the deficit, not the specific drug. Protein around 2 g/kg, holding your resistance training volume, and keeping loss to about 0.5-1% of body weight per week are what protect muscle.
References
- 1.A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management — New England Journal of Medicine (2015) PMID 26132939
- 2.Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes — New England Journal of Medicine (2016) PMID 27295427
More fat loss & metabolic
5-Amino-1MQ
Oral NNMT inhibitor aimed at fat-cell metabolism and NAD+ salvage. Mouse data only.
100 mg · once daily
AOD-9604
Modified hGH tail fragment sold for lipolysis without the IGF-1 rise of growth hormone.
300 mcg · once daily
Cagrilintide
Long-acting amylin analogue run weekly for satiety, usually alongside a GLP-1.
2.4 mg · once weekly
HGH Fragment 176-191
The C-terminal tail of growth hormone, sold for fat loss on almost entirely rodent evidence.
250 mcg · Once daily, fasted (many split it into two 250 mcg doses)