Semaglutide: Difference between revisions
| [unchecked revision] | [checked revision] |
MDElliottMD (talk | contribs) Fix Cargo VARCHAR(300) overflow: blank structure, shorten mechanism, move chemistry/mechanism prose to PK/PD |
MDElliottMD (talk | contribs) Strip Category:MedCategory marker per interface-claude 2026-05-20 hygiene order: this page is a medicine, narrative, wiki-meta page, or stylesheet rather than a class-overview category, so it should not carry the MedCategory tag. Class memberships and other tags preserved. |
||
| (3 intermediate revisions by the same user not shown) | |||
| Line 14: | Line 14: | ||
| onset = Glycemic effect within days;{{Citation needed}} full weight effect over months<ref name="step1">Wilding JPH et al. (2021). Once-weekly semaglutide in adults with overweight or obesity (STEP-1). ''NEJM'' 384:989. doi:10.1056/NEJMoa2032183</ref> | | onset = Glycemic effect within days;{{Citation needed}} full weight effect over months<ref name="step1">Wilding JPH et al. (2021). Once-weekly semaglutide in adults with overweight or obesity (STEP-1). ''NEJM'' 384:989. doi:10.1056/NEJMoa2032183</ref> | ||
| duration = ~7 days (weekly SC dosing)<ref name="ozempic-label"/> · ~24 h (oral)<ref name="rybelsus-label"/> | | duration = ~7 days (weekly SC dosing)<ref name="ozempic-label"/> · ~24 h (oral)<ref name="rybelsus-label"/> | ||
| halflife = ~165 hours (~1 week) | | halflife = ~165 hours (~1 week), among the longest of any GLP-1 RA<ref name="lau2015"/> | ||
| bioavailability = SC ~89%{{Citation needed}} · Oral ~0.4–1% (SNAC-enhanced)<ref name="rybelsus-label"/> | | bioavailability = SC ~89%{{Citation needed}} · Oral ~0.4–1% (SNAC-enhanced)<ref name="rybelsus-label"/> | ||
| pregnancy = Avoid. Discontinue ≥2 months before planned pregnancy due to long half-life. Animal data show embryofetal harm.<ref name="ozempic-label"/> Not contraceptive | | pregnancy = Avoid. Discontinue ≥2 months before planned pregnancy due to long half-life. Animal data show embryofetal harm.<ref name="ozempic-label"/> Not contraceptive, but rapid weight loss + improved ovulation may unmask fertility in [[PCOS]].{{Citation needed}} | ||
| legal = Rx-only;<ref name="ozempic-label"/> not a controlled substance | | legal = Rx-only;<ref name="ozempic-label"/> not a controlled substance | ||
| intro = Semaglutide is a long-acting [[GLP-1 receptor agonist]] developed by [[Novo Nordisk]], marketed as '''[[Ozempic]]''' (weekly subcutaneous, for [[type 2 diabetes mellitus]]),<ref name="ozempic-label"/> '''[[Wegovy]]''' (weekly subcutaneous, for [[obesity]], [[cardiovascular risk reduction]] in obesity without diabetes, and [[MASH]] with fibrosis),<ref name="wegovy-label"/><ref name="select">Lincoff AM et al. (2023). Semaglutide and cardiovascular outcomes in obesity without diabetes (SELECT). ''NEJM'' 389:2221–32. doi:10.1056/NEJMoa2307563</ref><ref name="essence">Newsome PN et al. (2025). Semaglutide in MASH (ESSENCE). FDA approval basis. {{Citation needed}}</ref> and '''[[Rybelsus]]''' (daily oral tablet, for T2DM).<ref name="rybelsus-label"/> It is, by revenue, among the highest-grossing medicines on the planet as of 2024.{{Citation needed}} | | intro = Semaglutide is a long-acting [[GLP-1 receptor agonist]] developed by [[Novo Nordisk]], marketed as '''[[Ozempic]]''' (weekly subcutaneous, for [[type 2 diabetes mellitus]]),<ref name="ozempic-label"/> '''[[Wegovy]]''' (weekly subcutaneous, for [[obesity]], [[cardiovascular risk reduction]] in obesity without diabetes, and [[MASH]] with fibrosis),<ref name="wegovy-label"/><ref name="select">Lincoff AM et al. (2023). Semaglutide and cardiovascular outcomes in obesity without diabetes (SELECT). ''NEJM'' 389:2221–32. doi:10.1056/NEJMoa2307563</ref><ref name="essence">Newsome PN et al. (2025). Semaglutide in MASH (ESSENCE). FDA approval basis. {{Citation needed}}</ref> and '''[[Rybelsus]]''' (daily oral tablet, for T2DM).<ref name="rybelsus-label"/> It is, by revenue, among the highest-grossing medicines on the planet as of 2024.{{Citation needed}} | ||
| Line 26: | Line 26: | ||
Acylation with a C18 fatty diacid drives non-covalent binding to serum albumin, slowing renal clearance and DPP-4 access. The Aib8 substitution renders the peptide DPP-4-resistant. Resulting terminal half-life ~165 h means once-weekly subcutaneous dosing produces near-steady-state plasma levels.<ref name="lau2015"/> | Acylation with a C18 fatty diacid drives non-covalent binding to serum albumin, slowing renal clearance and DPP-4 access. The Aib8 substitution renders the peptide DPP-4-resistant. Resulting terminal half-life ~165 h means once-weekly subcutaneous dosing produces near-steady-state plasma levels.<ref name="lau2015"/> | ||
Oral semaglutide (Rybelsus) is co-formulated with '''SNAC''' (sodium N-[8-(2-hydroxybenzoyl)amino]caprylate), a permeation enhancer that transiently raises gastric pH and protects the peptide locally | Oral semaglutide (Rybelsus) is co-formulated with '''SNAC''' (sodium N-[8-(2-hydroxybenzoyl)amino]caprylate), a permeation enhancer that transiently raises gastric pH and protects the peptide locally, yielding ~0.4–1% bioavailability, which is sufficient at 14 mg daily to match Ozempic 0.5 mg weekly for glycemic effect (but not for weight loss).<ref name="rybelsus-label"/><ref name="buckley2018">Buckley ST, Bækdal TA, Vegge A et al. (2018). Transcellular stomach absorption of a derivatized glucagon-like peptide-1 receptor agonist. ''Sci Transl Med'' 10(467):eaar7047. doi:10.1126/scitranslmed.aar7047</ref> Strict fasting administration is mandatory; any concurrent food or beverage destroys absorption.<ref name="rybelsus-label"/> | ||
Predominantly catabolic clearance via proteolysis; renal and hepatic impairment do not require dose adjustment.<ref name="ozempic-label"/> No CYP-mediated metabolism, so the interaction profile is dominated by ''gastric emptying'' effects on other oral medicines, not pharmacokinetic competition.<ref name="ozempic-label"/> | Predominantly catabolic clearance via proteolysis; renal and hepatic impairment do not require dose adjustment.<ref name="ozempic-label"/> No CYP-mediated metabolism, so the interaction profile is dominated by ''gastric emptying'' effects on other oral medicines, not pharmacokinetic competition.<ref name="ozempic-label"/> | ||
| Line 40: | Line 40: | ||
* 24% relative risk reduction in kidney + CV composite in T2DM + CKD (FLOW)<ref name="flow">Perkovic V et al. (2024). Effects of semaglutide on chronic kidney disease in patients with type 2 diabetes (FLOW). ''NEJM'' 391:109. doi:10.1056/NEJMoa2403347</ref> | * 24% relative risk reduction in kidney + CV composite in T2DM + CKD (FLOW)<ref name="flow">Perkovic V et al. (2024). Effects of semaglutide on chronic kidney disease in patients with type 2 diabetes (FLOW). ''NEJM'' 391:109. doi:10.1056/NEJMoa2403347</ref> | ||
| indications = < | | indications = <problem ref="diabetes-type-2" author="MDElliottMD"/> | ||
< | <problem ref="obesity" author="MDElliottMD"/> | ||
< | <problem ref="cv-risk-obesity" author="MDElliottMD"/> | ||
< | <problem ref="mash-fibrosis" author="MDElliottMD"/> | ||
< | <problem ref="ckd-t2dm" author="MDElliottMD"/> | ||
| dosing = <titration slug="ozempic-standard" author="MDElliottMD" title="Ozempic | | dosing = <titration slug="ozempic-standard" author="MDElliottMD" title="Ozempic, standard T2DM titration"> | ||
0.25 mg SC weekly × 4 weeks (non-therapeutic; tolerance ramp only) | 0.25 mg SC weekly × 4 weeks (non-therapeutic; tolerance ramp only) | ||
→ 0.5 mg SC weekly × ≥4 weeks | → 0.5 mg SC weekly × ≥4 weeks | ||
| Line 52: | Line 52: | ||
→ 2 mg SC weekly (max) if needed<ref name="ozempic-label"/> | → 2 mg SC weekly (max) if needed<ref name="ozempic-label"/> | ||
Slower titration is reasonable in any patient with significant GI symptoms | Slower titration is reasonable in any patient with significant GI symptoms, holding at a tolerated dose for 8–12 weeks before advancing is standard practice. | ||
</titration> | </titration> | ||
<titration slug="wegovy-standard" author="MDElliottMD" title="Wegovy | <titration slug="wegovy-standard" author="MDElliottMD" title="Wegovy, standard obesity titration"> | ||
0.25 mg SC weekly × 4 weeks | 0.25 mg SC weekly × 4 weeks | ||
→ 0.5 mg × 4 weeks | → 0.5 mg × 4 weeks | ||
| Line 65: | Line 65: | ||
</titration> | </titration> | ||
<titration slug="rybelsus-standard" author="MDElliottMD" title="Rybelsus | <titration slug="rybelsus-standard" author="MDElliottMD" title="Rybelsus, standard oral T2DM titration"> | ||
3 mg PO daily × 30 days (non-therapeutic ramp) | 3 mg PO daily × 30 days (non-therapeutic ramp) | ||
→ 7 mg PO daily × ≥30 days | → 7 mg PO daily × ≥30 days | ||
| Line 74: | Line 74: | ||
| effects = Subjective effects vary considerably with dose and titration speed but reliably include: | | effects = Subjective effects vary considerably with dose and titration speed but reliably include: | ||
* '''Early satiety''' | * '''Early satiety''', meals feel "complete" at a fraction of prior intake<ref name="step1"/> | ||
* '''Food noise quieting''' | * '''Food noise quieting''', the most commonly volunteered subjective change. Patients report that intrusive food-related thoughts simply stop.{{Citation needed}} | ||
* '''Reduced alcohol craving''' | * '''Reduced alcohol craving''', corroborated by observational and small RCT data; mechanism likely shared with food reward circuitry<ref name="wang2024">Wang W, Volkow ND, Berger NA et al. (2024). Associations of semaglutide with incidence and recurrence of alcohol use disorder in real-world population. ''Nat Commun'' 15:4548. doi:10.1038/s41467-024-48780-6</ref> | ||
* '''Nausea''' | * '''Nausea''', dose-dependent, worst in first 1–2 weeks of any new dose level<ref name="ozempic-label"/> | ||
* '''Constipation or diarrhea''' (variable, can alternate)<ref name="ozempic-label"/> | * '''Constipation or diarrhea''' (variable, can alternate)<ref name="ozempic-label"/> | ||
* '''Sulfurous eructation''' (a small but very real subgroup){{Citation needed}} | * '''Sulfurous eructation''' (a small but very real subgroup){{Citation needed}} | ||
| Line 90: | Line 90: | ||
Importantly: semaglutide is '''not a contraceptive''', and the medicine may '''restore ovulation''' in patients with [[PCOS]] or [[obesity]]-associated anovulation.{{Citation needed}} Patients of childbearing potential should be counseled about contraception ''before'' starting. | Importantly: semaglutide is '''not a contraceptive''', and the medicine may '''restore ovulation''' in patients with [[PCOS]] or [[obesity]]-associated anovulation.{{Citation needed}} Patients of childbearing potential should be counseled about contraception ''before'' starting. | ||
| monitoring = * Baseline: HbA1c, weight, BP, renal function, lipid panel, [[ALT]]/AST (especially for MASH | | monitoring = * Baseline: HbA1c, weight, BP, renal function, lipid panel, [[ALT]]/AST (especially for MASH problem) | ||
* Personal or family history of MTC or [[MEN2]] | * Personal or family history of MTC or [[MEN2]], '''contraindicated''', do not start<ref name="ozempic-label"/> | ||
* Every 3 months for first year: HbA1c, weight, GI tolerability, signs of [[pancreatitis]] or [[gallbladder disease]] | * Every 3 months for first year: HbA1c, weight, GI tolerability, signs of [[pancreatitis]] or [[gallbladder disease]] | ||
* Annual: renal function, lipids | * Annual: renal function, lipids | ||
| Line 99: | Line 99: | ||
* Inject SC in abdomen, thigh, or upper arm; rotate sites. Pen is single-patient, multi-dose.<ref name="ozempic-label"/> | * Inject SC in abdomen, thigh, or upper arm; rotate sites. Pen is single-patient, multi-dose.<ref name="ozempic-label"/> | ||
* GI side effects almost always peak in first 2–4 weeks of any new dose level, then attenuate.<ref name="ozempic-label"/> | * GI side effects almost always peak in first 2–4 weeks of any new dose level, then attenuate.<ref name="ozempic-label"/> | ||
* Eat smaller portions earlier in the day. Plate sizes will feel comically large after a few weeks | * Eat smaller portions earlier in the day. Plate sizes will feel comically large after a few weeks, that is the medicine working, not a problem to fix. | ||
* Hydrate aggressively (volume depletion → AKI is a real risk).<ref name="ozempic-label"/> | * Hydrate aggressively (volume depletion → AKI is a real risk).<ref name="ozempic-label"/> | ||
* Resistance training during weight loss protects lean mass and is strongly encouraged.{{Citation needed}} | * Resistance training during weight loss protects lean mass and is strongly encouraged.{{Citation needed}} | ||
| Line 117: | Line 117: | ||
}} | }} | ||
[[Category:GLP-1 receptor agonists]] | [[Category:GLP-1 receptor agonists]] | ||
[[Category:Antidiabetic medicines]] | [[Category:Antidiabetic medicines]] | ||
[[Category:Anti-obesity medicines]] | [[Category:Anti-obesity medicines]] | ||
[[Category:Novo Nordisk medicines]] | [[Category:Novo Nordisk medicines]] | ||
Latest revision as of 18:00, 19 May 2026
Experience
Log in to add your own experience.
Problems
Titration strategies
→ 0.5 mg SC weekly × ≥4 weeks → 1 mg SC weekly × ≥4 weeks if further glycemic control needed → 2 mg SC weekly (max) if needed[1]
Slower titration is reasonable in any patient with significant GI symptoms, holding at a tolerated dose for 8–12 weeks before advancing is standard practice.Effects
Subjective effects vary considerably with dose and titration speed but reliably include:
- Early satiety, meals feel "complete" at a fraction of prior intake[4]
- Food noise quieting, the most commonly volunteered subjective change. Patients report that intrusive food-related thoughts simply stop.[citation needed]
- Reduced alcohol craving, corroborated by observational and small RCT data; mechanism likely shared with food reward circuitry[8]
- Nausea, dose-dependent, worst in first 1–2 weeks of any new dose level[1]
- Constipation or diarrhea (variable, can alternate)[1]
- Sulfurous eructation (a small but very real subgroup)[citation needed]
- Reduced taste preference for fatty / sweet foods in many users[citation needed]
Pharmacokinetics
Chemistry. 31-amino-acid acylated peptide analog of human GLP-1 (7–37), with Aib substitution at position 8 (blocks DPP-4 cleavage) and a C18 fatty diacid linked via γGlu-2×OEG spacer at Lys26 (drives albumin binding → ~165 h half-life)[5]
Acylation with a C18 fatty diacid drives non-covalent binding to serum albumin, slowing renal clearance and DPP-4 access. The Aib8 substitution renders the peptide DPP-4-resistant. Resulting terminal half-life ~165 h means once-weekly subcutaneous dosing produces near-steady-state plasma levels.[5]
Oral semaglutide (Rybelsus) is co-formulated with SNAC (sodium N-[8-(2-hydroxybenzoyl)amino]caprylate), a permeation enhancer that transiently raises gastric pH and protects the peptide locally, yielding ~0.4–1% bioavailability, which is sufficient at 14 mg daily to match Ozempic 0.5 mg weekly for glycemic effect (but not for weight loss).[3][9] Strict fasting administration is mandatory; any concurrent food or beverage destroys absorption.[3]
Predominantly catabolic clearance via proteolysis; renal and hepatic impairment do not require dose adjustment.[1] No CYP-mediated metabolism, so the interaction profile is dominated by gastric emptying effects on other oral medicines, not pharmacokinetic competition.[1]Pharmacodynamics
Receptor pharmacology. Selective long-acting agonist of the GLP-1 receptor (class B GPCR). Produces glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, hypothalamic appetite suppression, and direct cardiovascular and renal protective effects.[10]
At maintenance doses semaglutide produces:
- HbA1c reduction of ~1.5–2.0 percentage points (Ozempic 1 mg)[11]
- Weight loss of ~6 kg (Ozempic 1 mg, T2DM)[11] to ~14.9% body weight (Wegovy 2.4 mg, obesity without T2DM, STEP-1)[4]
- Systolic BP reduction of ~5 mmHg[6]
- Modest LDL-C reduction, larger triglyceride reduction[citation needed]
- 20% relative risk reduction in MACE in obesity without T2DM (SELECT)[6]
- 24% relative risk reduction in kidney + CV composite in T2DM + CKD (FLOW)[12]
Interactions
Pregnancy and lactation
Category formerly X-equivalent; current FDA labeling: avoid in pregnancy.[1] Animal embryofetal toxicity is well-documented.[1] Because the half-life is ~1 week, current guidance is to discontinue at least 2 months before any planned conception.[1]
Postpartum: not recommended during breastfeeding pending more data; small molecule transfer to milk is unlikely given peptide structure but not formally characterized.[citation needed]
Importantly: semaglutide is not a contraceptive, and the medicine may restore ovulation in patients with PCOS or obesity-associated anovulation.[citation needed] Patients of childbearing potential should be counseled about contraception before starting.Monitoring
- Baseline: HbA1c, weight, BP, renal function, lipid panel, ALT/AST (especially for MASH problem)
- Personal or family history of MTC or MEN2, contraindicated, do not start[1]
- Every 3 months for first year: HbA1c, weight, GI tolerability, signs of pancreatitis or gallbladder disease
- Annual: renal function, lipids
- Pre-procedure: hold weekly dose ≥7 days before any planned anesthesia (per ASA 2024 guidance) due to delayed gastric emptying / aspiration risk[13]
Patient counseling
- Slow titration is non-negotiable for tolerability. Patients who insist on faster ramps usually quit from GI side effects.
- Inject SC in abdomen, thigh, or upper arm; rotate sites. Pen is single-patient, multi-dose.[1]
- GI side effects almost always peak in first 2–4 weeks of any new dose level, then attenuate.[1]
- Eat smaller portions earlier in the day. Plate sizes will feel comically large after a few weeks, that is the medicine working, not a problem to fix.
- Hydrate aggressively (volume depletion → AKI is a real risk).[1]
- Resistance training during weight loss protects lean mass and is strongly encouraged.[citation needed]
- If a weekly dose is missed: take within 5 days; if >5 days, skip and resume on the next regular day.[1]
- Avoid alcohol during titration weeks (compounds nausea).
- Pregnancy planning: stop ≥2 months before trying to conceive.[1]
- Surgery: tell every anesthesiologist and surgeon you are on a weekly GLP-1 RA. Hold dose 7 days pre-op.[13]
Relevant anecdote
0 0 0 0
Relevant Literature
No literature entries yet.
Log in to submit relevant literature.
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 US FDA. Ozempic (semaglutide) prescribing information. Novo Nordisk. https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/209637s019lbl.pdf
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 US FDA. Wegovy (semaglutide) prescribing information. Novo Nordisk. https://www.accessdata.fda.gov/drugsatfda_docs/label/2021/215256s000lbl.pdf
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 US FDA. Rybelsus (semaglutide) prescribing information. Novo Nordisk. https://www.accessdata.fda.gov/drugsatfda_docs/label/2019/213051s000lbl.pdf
- ↑ 4.0 4.1 4.2 Wilding JPH et al. (2021). Once-weekly semaglutide in adults with overweight or obesity (STEP-1). NEJM 384:989. doi:10.1056/NEJMoa2032183
- ↑ 5.0 5.1 5.2 5.3 Lau J, Bloch P, Schäffer L et al. (2015). Discovery of the once-weekly glucagon-like peptide-1 (GLP-1) analogue semaglutide. J Med Chem 58(18):7370–80. doi:10.1021/acs.jmedchem.5b00726
- ↑ 6.0 6.1 6.2 Lincoff AM et al. (2023). Semaglutide and cardiovascular outcomes in obesity without diabetes (SELECT). NEJM 389:2221–32. doi:10.1056/NEJMoa2307563
- ↑ Newsome PN et al. (2025). Semaglutide in MASH (ESSENCE). FDA approval basis. [citation needed]
- ↑ Wang W, Volkow ND, Berger NA et al. (2024). Associations of semaglutide with incidence and recurrence of alcohol use disorder in real-world population. Nat Commun 15:4548. doi:10.1038/s41467-024-48780-6
- ↑ Buckley ST, Bækdal TA, Vegge A et al. (2018). Transcellular stomach absorption of a derivatized glucagon-like peptide-1 receptor agonist. Sci Transl Med 10(467):eaar7047. doi:10.1126/scitranslmed.aar7047
- ↑ Drucker DJ (2022). GLP-1 physiology informs the pharmacotherapy of obesity. Mol Metab 57:101351. doi:10.1016/j.molmet.2021.101351
- ↑ 11.0 11.1 Marso SP et al. (2016). Semaglutide and cardiovascular outcomes in patients with type 2 diabetes (SUSTAIN-6). NEJM 375:1834–44. doi:10.1056/NEJMoa1607141
- ↑ Perkovic V et al. (2024). Effects of semaglutide on chronic kidney disease in patients with type 2 diabetes (FLOW). NEJM 391:109. doi:10.1056/NEJMoa2403347
- ↑ 13.0 13.1 Kindel TL et al. (2024). Perioperative GLP-1 receptor agonist safety guidance. Surg Obes Relat Dis 20(12):1183–8.