Human RCT
Mensch, multizentrische RCT
Marso SP et al. 2016
Reduction of HbA1c in type-2 diabetes
What does NOT follow: Effect well established in randomised trials; individual response varies with baseline HbA1c, co-medication and adherence.
Peptide entry · Metabolic
Semaglutid
Semaglutide · Ozempic · Wegovy
Highest evidence
Human RCT
Studies recorded
4· 3 in humans
Legal status · US
PrescriptionScientific context only. Not medical advice, not a recommendation to use.
At a glance
Long-acting GLP-1 receptor agonist. Approved as a medicinal product for type-2 diabetes (Ozempic, Rybelsus), chronic weight management (Wegovy) and cardiovascular risk in obesity. One of the best-studied substances on this platform — many large human RCTs.
Researched for
Type-2 diabetesObesity / weight managementCardiovascular riskMetabolic regulation
Official status
US: Prescription
FDA-approved for type-2 diabetes (2017, Ozempic), chronic weight management (2021, Wegovy) and cardiovascular risk (2024, SELECT indication extension).
01
Mechanism of action
Long-acting agonist at the GLP-1 receptor. Structurally a modified glucagon-like peptide 1 whose long half-life is achieved via a fatty-acid side chain and reversible albumin binding. Acts centrally on satiety and peripherally on glucose-dependent insulin secretion and delayed gastric emptying.
02
Evidence at a glance
Reading note. The distribution shows on which evidence tier each observation sits. Strong colours mark stronger evidence — weaker tiers are deliberately visible, not hidden.
03
What the studies show
Human RCT
Mensch, STEP-Programm
Wilding JPH et al. 2021
Weight reduction in overweight and obesity
What does NOT follow: Substantial mean reduction in RCTs; weight regain after discontinuation is published and should be considered.
Human RCT
Mensch, SELECT-Studie
Lincoff AM et al. 2023
Reduction of cardiovascular events in obesity without diabetes
What does NOT follow: Relative risk reduction in a high-risk population; absolute effect size context-dependent.
04
Where studies disagree
Open question
Is weight loss maintained after discontinuation?
POSITION A
STEP follow-up publications show substantial regain after discontinuation without continued treatment.
POSITION B
With continued lifestyle intervention and maintenance protocols, part of the weight loss may be retained.
CURRENT STATE · Regain after discontinuation is the rule, not the exception. The substance is designed for chronic therapy.
05
Pharmacokinetics
Theoretical concentration curve at a half-life of 165 h. Pure pharmacokinetic model — not a dosing recommendation.
Open in PK tool →Start time: t₀ = 0.0d
Repeat interval: off (single dose)
06
Routes of administration in the literature
Which routes of administration the available studies describe — neutral reporting, not a usage guide.
Subcutaneous
Standard route as weekly injection in trials and approved indications.
Oral
Oral tablet form (Rybelsus) with a dedicated absorption enhancer (SNAC) studied in the PIONEER programme.
06b
Amounts reported in sources
Which amounts were reported in which source — ordered by context (approval, trial, animal model, secondary literature, community).
06c
Storage & stability
What prescribing information and stability literature report about storing the substance — descriptive, not a mixing or usage guide.
Reconstituted · storage
Unopened pen: 2–8 °C (refrigerator), protected from light; do not freeze.
Reconstituted · shelf life
After first use: up to 56 days at 2–8 °C or below 30 °C (Ozempic label).
What the stability literature describes
- •Freezing destroys semaglutide — the label describes frozen pens as no longer usable.
- •Keep protected from direct light and heat.
- •The label describes marking the pen with the date of first use.
07
Known adverse events from studies
Factual reporting of what studies observed. Not a safety statement for individual use.
Human RCT
Adults, RCTs
Nausea
Reported as the most common adverse event in large RCTs; mostly in early weeks, often transient.
häufig / common
Human RCT
Vomiting
Correlates with the gastrointestinal mechanism of action.
häufig / common
Human trial
Pancreatitis
Signal in pharmacovigilance and individual studies; low absolute frequency, causal link under debate.
selten / rare
Human RCT
Gallbladder disease
Increased risk observed across multiple RCTs; mechanistically consistent with delayed gallbladder emptying.
ungewöhnlich / uncommon
Animal model
Thyroid C-cell tumour
Observed in rodent models; human relevance not established. Nevertheless an FDA boxed warning.
nicht etabliert beim Menschen
07b
Interactions & combinations
Documented interactions and contraindications from studies, prescribing information and guidelines. Where no data exists, this is stated.
Reporting of risks, NOT a combination guide. The absence of an entry does not mean „safe to combine“ but „not sufficiently studied“.
CautionInsulin / sulfonylureasHuman RCT
Increased risk of hypoglycaemia when combined; insulin/SU doses were adjusted in trials.
Context: Risk reporting from the label, not a combination guide.
MonitorOrally administered medications (general)Human trial
Delayed gastric emptying can affect the absorption of orally administered drugs.
Context: General label note; clinical relevance depends on the specific drug.
08
Risks & hygiene aspects in the literature
What regulatory and scientific literature reports on risks, sterility and identity in non-pharmaceutical sources — descriptive, not a hygiene guide.
Compounding following FDA shortage declaration
During the FDA-declared shortage in 2023–2024, compounding was temporarily permitted. After resolution of the shortage, compounding sources have been restricted again; regulators repeatedly cite identity, sterility and purity problems with non-pharmaceutical sources.
Grey market for unapproved semaglutide
Analyses of regulator-flagged grey-market products show deviations in identity, concentration and impurities — relevant for the risk discussion outside approved use.
09
Regulatory voices
Direct statements from official assessment documents — paraphrased with date and source link.
FDAU.S. Food and Drug Administration
2017-12Boxed warning — risk of thyroid C-cell tumours
The FDA prescribing information carries a boxed warning on thyroid C-cell tumours based on rodent-model findings. Human relevance of these findings is not established. Personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2 is a contraindication.
EMAEuropean Medicines Agency
2018-02Authorisation decision for Ozempic (subcutaneous) — type-2 diabetes indication
The EMA authorised Ozempic for the treatment of adults with insufficiently controlled type-2 diabetes as an adjunct to diet and exercise — as monotherapy or in combination with other antidiabetic medicinal products.
10
Anecdotal observations
Weakest evidence tier — not supported by studies
Reading note. This section gathers popular claims from communities and forums. They are explicitly marked as weakest-tier evidence. Unblinded self-reports are particularly prone to placebo, recall and confirmation biases.
Why no amounts or protocols are listed here. We deliberately show only WHAT communities report — not in what amount or how it is used. Anecdotal "doses" or "biohacker protocols" are neither verified nor standardised nor safe; publishing them would be a usage guide, which we do not provide on principle. Specific amounts belong in a conversation with a doctor, not in a forum.
“Ozempic face”: subjective perception of facial volume loss
Widely discussed in media and social networks.
Not supported by studies: Likely a consequence of weight loss itself, not the substance. No controlled studies on specific facial changes.
Off-label use for “lifestyle weight loss” without obesity
Widespread in social-media reports.
Not supported by studies: Use outside approved indications. Benefit-risk profile not established by RCTs in this population.
10b
What online communities discuss
Recurring themes from Reddit, Quora and patient forums — synthetically summarised, sources linked. Not scientific evidence, but a signal of what users report. Deliberately separated from the study base.
Non-scientific sources. What users report in forums — synthetically summarised, paraphrased, with link to source. Not validated by studies.
Sorted by discussion frequency · 3 Themen
11
Legal status by country
12
Reconstitution calculator
Pure mg/mL maths — works like a calculator. Not a usage recommendation.
Peptides ship as a dry powder. Once dissolved in a liquid (reconstitution), this calculator answers a single question: how much substance is in one millilitre of solution afterwards?
- 1Enter the vial's substance amount (printed on the label).
- 2Enter how much solvent you add.
- 3Result = concentration in mg per mL.
Printed on the label
/
Liquid you add
=
2.50
mg / mL
5 mg in 2 mL gives 2.50 mg/mL — each millilitre contains 2.50 mg of substance.
14
Study register
Human RCTRandomised controlled trialn = 1961
Wilding JPH et al. · 2021
Once-Weekly Semaglutide in Adults with Overweight or Obesity
SampleAdults with overweight/obesity without diabetes over 68 weeks.
EndpointPercentage change in body weight.
MethodOnce-weekly subcutaneous administration with titration from 0.25 mg to 2.4 mg over 16 weeks, then maintenance through week 68. Concurrent lifestyle intervention in both arms.
Concrete results
Mean weight loss
−14.9%
vs. −2.4% Placebo · 68 Wochen
Participants achieving ≥ 5% weight loss
86.4%
vs. 31.5% Placebo · 68 Wochen
Participants achieving ≥ 10% weight loss
69.1%
vs. 12.0% Placebo · 68 Wochen
Participants achieving ≥ 15% weight loss
50.5%
vs. 4.9% Placebo · 68 Wochen
Findings:Clinically meaningful weight loss vs. placebo with concurrent lifestyle intervention.
Limitations:Limited observation period; weight regain after discontinuation documented in follow-up publications.
Human RCTRandomised controlled trialn = 3297
Marso SP et al. · 2016
Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes
SampleAdults with type-2 diabetes and elevated cardiovascular risk.
MethodOnce-weekly subcutaneous 0.5 mg or 1.0 mg versus placebo. Median follow-up 2.1 years.
Concrete results
Composite cardiovascular endpoint (MACE)
6.6%
vs. 8.9% Placebo (HR 0.74) · 2.1 Jahre Median
Non-fatal stroke
1.6%
vs. 2.7% Placebo · 2.1 Jahre Median
HbA1c reduction
−1.1 bis −1.4 Prozentpunkte
vs. Placebo · Studiendauer
Findings:Reduction of composite cardiovascular endpoints vs. placebo in high-risk patients.
Human RCTRandomised controlled trialn = 17604
Lincoff AM et al. · 2023
Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes
SampleAdults with established cardiovascular disease and obesity, without diabetes.
MethodOnce-weekly subcutaneous 2.4 mg after titration. Mean follow-up 39.8 months.
Concrete results
Composite cardiovascular endpoint (MACE)
6.5%
vs. 8.0% Placebo (HR 0.80) · 39.8 Monate Mittel
Mean weight loss
−8.51%
vs. −1.50% Placebo · 104 Wochen
All-cause death
4.3%
vs. 5.2% Placebo · 39.8 Monate Mittel
Findings:Statistically significant reduction of the primary cardiovascular endpoint.
Animal modelAnimal model
U.S. Food and Drug Administration · 2017
FDA Boxed Warning — Risk of Thyroid C-Cell Tumors
Findings:Thyroid C-cell tumours in rats under GLP-1 analogues; human relevance not established.
15
Sources & method
Reviewed by
Dr. [Placeholder]
Last reviewed
2026-05-21
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