Has anyone compared Saxenda and Xenical in the same trial?

No head-to-head trial has compared these two drugs. Saxenda's figures come from SCALE Obesity and Prediabetes (56 weeks) and Xenical's from Sjostrom 1-year RCT (52 weeks), which enrolled different people for different lengths of time. Numbers from separate trials can be read side by side, but they are not a measured difference.

How much weight did people lose on each?

In clinical trials, participants taking liraglutide lost on average up to 8% of their starting body weight (SCALE Obesity and Prediabetes, 56 weeks), and participants taking orlistat lost on average up to 8.5% (Sjostrom 1-year RCT, 52 weeks). Both figures are averages in each drug's main trial; individual results in those trials varied widely.

What does each one cost per month?

Saxenda is listed at $1,000–$1,349/month. Xenical is listed at $40–$400/month (over-the-counter strength; prescription runs to $400). The full price note for each is set out in the cost section above. What you pay depends on your insurance, your dose and your pharmacy.

Can I switch from Saxenda to Xenical?

Switching between weight-loss medicines is a decision for the prescriber who knows your history, your other medicines and how you have responded so far — this site cannot make it for you. What switching involves in practice, including dose steps and the gap between drugs, is set out on the switching page.

Which side effects were reported most often?

In SCALE Obesity and Prediabetes (56 weeks), the reaction reported most often with liraglutide was nausea — 40% of participants. In XENDOS (208 weeks), the reaction reported most often with orlistat was oily/fatty stools (steatorrhoea) — 27% of participants. Rates come from different trials with different participants, and a rate is not a prediction for any one person.

Saxenda vs Xenical: trials compared

At a glance

Saxenda and Xenical compared on form, trial results, cost and reported side effects
	Saxenda	Xenical
Form	Daily injection	3x daily with meals
How often	Daily injection	Three capsules daily, taken with each fat-containing meal
Weight loss in trials	Up to 8% — SCALE Obesity and Prediabetes (56 weeks)	Up to 8.5% — Sjostrom 1-year RCT (52 weeks)
FDA approved	2014	1999
Made by	Novo Nordisk	Roche (Xenical) / GSK (Alli OTC)
How it works	A GLP-1 analogue with a half-life of approximately 13 hours (requiring daily injection).	Blocks pancreatic lipase enzymes in the small intestine, preventing approximately 30% of dietary fat from being broken down and absorbed.
Monthly cost, self-pay	$1,000–$1,349/mo	$40–$400/moover-the-counter strength; prescription runs to $400
Most reported reaction	Nausea 40% (SCALE Obesity and Prediabetes)	Oily/fatty stools (steatorrhoea) 27% (XENDOS)

Every figure in this table is read from the same trial and label records used everywhere else on this site.

Weight loss in each drug's main trial

No head-to-head trial has compared these two drugs.

Saxenda(liraglutide)8%

SCALE Obesity and Prediabetes (56 weeks)

Xenical(orlistat)8.5%

Sjostrom 1-year RCT (52 weeks)

In clinical trials, participants taking liraglutide lost on average up to 8% of their starting body weight, and participants taking orlistat lost on average up to 8.5%. Those numbers come from two different studies: SCALE Obesity and Prediabetes enrolled 3,731 adults with obesity or overweight with comorbidities over 56 weeks against placebo, while Sjostrom 1-year RCT enrolled 743 adults with obesity over 1 year (52 weeks) against placebo. Who took part, how long each trial ran and what each drug was measured against all move the percentage, so the two figures are not a measured difference between the drugs.

Monthly cost, self-pay

The bar spans the range in each drug's price record — lowest listed price to highest.

Saxenda$1,000–$1,349/mo

Brand (Saxenda) ~$1,000–$1,349/month. Generic liraglutide is typically $135–$200 less than brand.

Xenical$40–$400/mo

over-the-counter strength; prescription runs to $400

Prescription Xenical ~$200–$400/month; over-the-counter Alli (60mg) ~$40–$60/month.

Self-pay prices are what the manufacturer or the pharmacy lists, not what most people end up paying. Saxenda: $1,000–$1,349/month. Xenical: $40–$400/month. Insurance, dose and pharmacy all change both figures.

Side effects reported in the trials

SCALE Obesity and Prediabetes and XENDOS did not report the same reactions, so there is no shared row to line up. Each drug's own reported rates are listed below.

Saxenda

Nausea40%
Diarrhoea21%
Constipation19%
Vomiting16%

From SCALE Obesity and Prediabetes

Xenical

Oily/fatty stools (steatorrhoea)27%
Faecal urgency22%
Oily spotting on underwear27%
Faecal incontinence8%
Abdominal pain/discomfort14%

From XENDOS

A rate is the share of trial participants who reported that reaction, not a prediction for any one person.

How they differ in practice

How you take it

Saxenda — Once-daily subcutaneous injection
Xenical — Oral capsule 120 mg, three times daily with meals (prescription). Also available OTC as Alli at 60 mg.

Dose build-up

Saxenda — 0.6 mg → 3.0 mg, escalated over 4 weeks

Where a drug is not listed here, its prescribing information sets out its own dose steps.

How soon it acts

Saxenda — Effects visible within 4–8 weeks; maximum benefit typically by 56 weeks
Xenical — Weight effects begin from the first week (related to calorie malabsorption), but significant loss takes 8–12 weeks

Heart and metabolic findings

Saxenda — The LEADER trial (type 2 diabetes) showed cardiovascular benefit.
Xenical — In the 4-year XENDOS trial, orlistat reduced progression from prediabetes to type 2 diabetes by 37% compared to placebo plus lifestyle changes.

As stated in each drug’s trial record — not a claim about which drug protects the heart more.

Other findings recorded

Saxenda — Approved for adolescents aged 12 and over (SCALE teens programme); generic liraglutide now available (Teva, August 2025) — reducing out-of-pocket cost
Xenical — 37% reduction in progression to type 2 diabetes (XENDOS, 4 years); only approved obesity drug with a 4-year safety dataset

If you stop taking it

Saxenda — Weight regain after stopping is expected, as with other GLP-1 drugs.
Xenical — Weight is typically regained after stopping.

Common questions

Written and maintained by one person · Built with agentic AI tools · Every number checked against the cited trial · Not medical advice

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Last reviewed: September 2026

Medical disclaimer: This website is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any treatment.