Semaglutide
Semaglutide is a GLP-1 (glucagon-like peptide-1) receptor agonist originally developed for type 2 diabetes and now FDA-approved for chronic weight management under the brand names Ozempic and Wegovy. It mimics the incretin hormone GLP-1, slowing gastric emptying, reducing appetite at the hypothalamic level, and improving insulin sensitivity. Clinical trials (STEP program) demonstrated average weight loss of 15-17% of body weight over 68 weeks. Semaglutide has also shown cardiovascular benefits, reducing major adverse cardiovascular events by 20%. It is administered as a once-weekly subcutaneous injection with a slow dose titration schedule to minimize GI side effects.
Frequency
Once weekly, same day each week
Cycle Length
Ongoing under medical supervision. Minimum 16 weeks to assess efficacy. Weight regain is common upon discontinuation.
Route
Subcutaneous
Research Level
Established
Goals
Dosing Protocol
Titrate up from 250 mcg to 2.5 mg weekly. Starting dose is 250 mcg. Compounded vials vary — with a typical 5 mg vial reconstituted in 1 mL, 0.5 mg = 10 units on a U-100 insulin syringe.
Timing
Same day every week. Starting dose is 250 mcg.
Get complete, interactive protocols in the PepStack Pro app.
Potential Side Effects
- Nausea (most common, usually transient)
- Vomiting
- Diarrhea or constipation
- Abdominal pain
- Decreased appetite
- Fatigue
- Injection site reactions
- Muscle loss — mitigate with regular strength training and a high-protein diet
- Rare: pancreatitis
- Gallbladder issues (risk increases with rapid weight loss)
- Contraindicated with personal or family history of medullary thyroid carcinoma (MTC)
Important Warnings
- Contraindicated with personal or family history of medullary thyroid carcinoma (MTC)
- Do not use with personal history of pancreatitis
- Weight regain is common upon discontinuation
- Prioritize protein intake and resistance training to minimize muscle loss
- Not for use during pregnancy
Works Well With
Research References
- Wilding JPH, et al. N Engl J Med. 2021;384(11):989-1002. doi:10.1056/NEJMoa2032183
- Lincoff AM, et al. N Engl J Med. 2023;389(24):2221-2232. doi:10.1056/NEJMoa2307563
Not sure which peptides are right for you?
Take our free protocol quiz to get personalized recommendations based on your goals.
Get Full Protocols in the App
Unlock interactive dosing calculators, injection tracking, stacking guides, and lab monitoring for Semaglutide and 60+ other peptides.
Connect with a Physician
Work with a board-certified physician who specializes in peptide therapy through MyFlowMD. Get a personalized Semaglutide protocol.
Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. Semaglutide may be regulated differently in various jurisdictions. Always consult with a qualified healthcare provider before beginning any peptide protocol. PepStack Pro does not sell peptides or provide medical advice. Content reviewed by Dr. Seth Miller, MD.