Semaglutide

Quickstart highlights

Dosing & reconstitution guide

Standard protocol (2 mL = 2,5 mg/mL)

A 5 mg vial dissolved in 2 mL bacteriostatic water gives a concentration of 2,5 mg/mL. Calculate your own dilution →

Reconstitution steps

1. Let the vial reach room temperature and wash your hands.
2. Disinfect both rubber stoppers with an alcohol swab.
3. Draw up 2 mL of bacteriostatic water.
4. Inject the water slowly down the glass wall, not directly onto the powder.
5. Swirl gently until clear — never shake.
6. Label the vial with date and concentration and refrigerate.

Supplies needed

• Semaglutide vial (5 mg)
• Bacteriostatic water
• Mixing syringe (1–3 mL) and U-100 insulin syringes
• Alcohol swabs and sharps container

Protocol overview

Dosing protocol in research

Values as described in literature and research protocols; not dosing advice.

Storage instructions

• Lyophilised (powder): cool, dry and dark; long-term at −20 °C.
• After reconstitution: refrigerator at 2–8 °C, use within ~4 weeks.
• Avoid repeated freezing and thawing.

Important notes

How this works

Semaglutide is a synthetic peptide that mimics the human gut hormone GLP-1. Originally developed to treat type 2 diabetes, it is now studied globally for obesity management. The compound is registered as an official medicine for these indications.

The peptide shares 94% sequence homology with human GLP-1. It binds to GLP-1 receptors in the brain to stimulate satiety and slow gastric emptying. In the pancreas, it triggers insulin release only when blood glucose levels rise. Due to albumin binding and structural modifications, semaglutide resists degradation by the DPP-4 enzyme. This results in a half-life of approximately seven days. Consequently, blood levels remain stable with once-weekly administration.

Phase 3 clinical trials show that participants with obesity lose an average of 10% to 15% body weight at a weekly 2.4 mg dose alongside lifestyle interventions. The compound is approved by the EMA and FDA for medical use, though it is on the WADA monitoring list for specific sports categories. Current research focuses on cardiovascular outcomes and fatty liver disease. Many studies utilize a gradual 16-week titration schedule to improve tolerability. Questions regarding muscle mass preservation and weight maintenance after cessation remain subjects of ongoing study.

Potential benefits & side effects

Effects described in research

• Reduced appetite and food intake
• Improved blood glucose control
• Cardiovascular risk reduction (SELECT trial)

Common side effects

• Nausea and reduced appetite
• Diarrhoea or constipation
• Belching, bloating
• Rare: pancreatitis, gallstones

Gastrointestinal issues such as nausea, vomiting, and constipation are most frequently reported, particularly during titration. Rare but serious side effects in literature include pancreatitis and gallbladder issues. There is limited data on long-term effects spanning several decades of use.

Contraindications

• Personal/family history of medullary thyroid cancer or MEN2
• History of pancreatitis
• Pregnancy or breastfeeding
• Type 1 diabetes

Lifestyle factors

• Smaller, protein-rich meals reduce GI complaints.
• Stay well hydrated; dehydration worsens nausea and constipation.
• Resistance training helps preserve lean mass during weight loss.
• Limit alcohol and very fatty meals.

Injection technique

• Choose a site with subcutaneous fat: abdomen (5 cm from the navel), thigh or back of upper arm.
• Disinfect, pinch a skin fold and insert at a 45–90° angle.
• Inject slowly, wait 5 seconds and withdraw.
• Rotate sites and use each needle once.

Recommended source

Quality varies widely between suppliers. Look for an independent HPLC/MS lab report per batch, purity ≥ 98% and clear storage and shipping conditions.

As a reference we use the Semaglutide from PeptideWinkel, which publishes lab reports per batch.

Frequently asked questions