What it does
Semaglutide activates the GLP-1 receptor to slow gastric emptying, suppress appetite, and improve insulin secretion. It is FDA-approved as Ozempic (T2D, 2017), Wegovy (chronic weight management, 2021), and Rybelsus (oral T2D, 2019). The SUSTAIN, STEP, and SELECT trial programs together include tens of thousands of participants and remain the gold-standard human evidence for any peptide-based intervention discussed in this library.
Used for
Dose
- Starting
- 250 mcg · once weekly
- Common
- 1,325 mcg · once weekly
- Upper
- 2,400 mcg · once weekly
- When
- MorningOnce-weekly. Time-of-day flexible across the week, but pick a consistent slot for adherence. GI side-effects most tolerable when the user's eating pattern is on a normal weekday schedule.
- How long
- Continuous (no on/off cycling) on / — off
- Site
- subcutaneous
- Food
- any
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⚠ Caution
- Personal or family history of medullary thyroid carcinoma (boxed warning)
- Multiple Endocrine Neoplasia syndrome type 2 (boxed warning)
- Hypersensitivity to semaglutide or excipients
- Pregnancy: avoid; discontinue 2 months before planned conception
- Caution: history of pancreatitis, severe gastroparesis, gallbladder disease
Medications & conditions
- Semaglutide with insulin or sulfonylurea — hypoglycemia riskAdding semaglutide to insulin or sulfonylurea therapy materially increases hypoglycemia risk. Clinical guidelines recommend reducing the dose of the concurrent agent when initiating GLP-1 therapy. Do not start without prescriber supervision.
Will it work for me?
Establish a baseline (2–3 readings over 1–2 weeks before starting), then track at consistent intervals.
Blood markers
- Tier 1 — Human RCTHbA1c↓· repeat at 3 months
- Tier 1 — Human RCTFasting glucose↓· by 8–12 weeks
- Tier 1 — Human RCTFasting insulin↓· by 12 weeksSecondary metabolic marker; improves as insulin sensitivity recovers.
- Tier 1 — Human RCTTriglycerides (lipid panel)↓· 12 weeks
Functional & psychometric
- Tier 3 — Animal / in vitroBody weight↓· tracked weekly; ~1–2 lb/week early; STEP-1 magnitude ~15% at 68 weeksScale-based; the primary real-world signal.
- Tier 3 — Animal / in vitroBlood pressure↓· 8–12 weeksTarget reduction ~3–5 mmHg.
- Tier 3 — Animal / in vitroWaist circumference↓· 12 weeksTape-measure proxy for central adiposity.
Your stack
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