Peptide profile
Semaglutide
GLP-1 receptor agonist for appetite suppression · also known as Ozempic, Wegovy, Rybelsus
Compare Semaglutide with other peptides →Summary
A GLP-1 receptor agonist approved for type 2 diabetes management and chronic weight management, demonstrating substantial and sustained weight reduction in large clinical trials.
- Typical dose
- 0.25 mg/week (starting), titrated to 2.4 mg/week (weight management)
- Half-life
- ~7 days
- Route
- Subcutaneous
- Cycle length
- Ongoing (approved for chronic use); titration over 16-20 weeks
Mechanism
How it works
Mimics endogenous glucagon-like peptide-1 (GLP-1), binding to GLP-1 receptors in the pancreas, brain, and gut. Increases insulin secretion in a glucose-dependent manner, suppresses glucagon, slows gastric emptying, and reduces appetite via hypothalamic signaling.
Reported in research
Benefits
- Clinically significant weight loss (15-20% body weight in trials)
- Improved glycemic control in type 2 diabetes
- Reduced cardiovascular risk in diabetic populations
- Reduced appetite and caloric intake
- Potential reduction in liver fat (NAFLD/MASH)
Context, not a prescription
Dosing
- Typical range
- 0.25 mg/week (starting), titrated to 2.4 mg/week (weight management) (Subcutaneous)
- Cycle length
- Ongoing (approved for chronic use); titration over 16-20 weeks
- Half-life
- ~7 days
Safety
Side effects & contraindications
Possible side effects
- Nausea (most common, especially during titration)
- Vomiting and diarrhea
- Constipation
- Fatigue
- Injection-site reactions
- Muscle loss (lean mass reduction alongside fat loss)
Contraindications
- Personal or family history of medullary thyroid carcinoma
- Multiple endocrine neoplasia type 2 (MEN2)
- Severe gastrointestinal disease
- Pancreatitis history (use with caution)
- Pregnancy
Research information, not medical advice. Always consult a licensed clinician before considering any peptide.
In depth
Full profile
What it does
You feel less hungry, your food digests slower, your blood sugar is lower, and you slowly lose weight.
How it works
Semaglutide is like a thermostat for hunger. It tells your brain you're full and tells your stomach to empty slowly.
It turns on GLP-1 switches in your pancreas, brain, and gut. This controls your blood sugar and hunger.
What to expect
You feel less hungry within days. You lose a lot of weight by 8-12 weeks.
- Week 1: You feel less hungry. You might feel a little sick to your stomach.
- Weeks 2-4: The dose slowly goes up. You keep losing weight.
- Weeks 8-12: You keep losing weight and your blood sugar gets better.
Good to know
- Start with the smallest dose (0.25mg)
- Eat smaller meals with less fat
- Drink plenty of water
Staying safe
- Feeling sick to your stomach (up to 40%)
- Throwing up
- Diarrhea
- Constipation (trouble going to the bathroom)
Avoid if you have:
- People who or whose family had a certain thyroid cancer
- People with a condition called MEN-2 syndrome
- People who are pregnant or breastfeeding
Mechanism of action
GLP-1 receptor agonist that stimulates insulin secretion, lowers glucagon, and delays gastric emptying.
Activates GLP-1 receptors in pancreas, brain, and gut to regulate glucose and hunger.
Pharmacodynamics
Appetite suppression within days; significant weight loss by 8-12 weeks.
Reduced hunger, slower digestion, lower blood sugar, progressive weight loss.
Timeline
- Week 1: Initial appetite reduction and possible mild nausea.
- Weeks 2-4: Gradual dose escalation and continued weight loss.
- Weeks 8-12: Progressive weight loss and glycemic improvement.
Comparisons
- Semaglutide — effectiveness Very High, safety Good, cost $$$, Easy to use
- Tirzepatide — effectiveness Very High, safety Good, cost $$$, Easy to use
Adverse effects
Common:
- Nausea (up to 40%)
- Vomiting
- Diarrhea
- Constipation
Rare:
- Pancreatitis
- Gallbladder disease
- Severe allergic reaction
Contraindications & risk mitigation
Contraindicated in:
- Personal/family history of medullary thyroid carcinoma
- MEN-2 syndrome
- Pregnancy or breastfeeding
- Start at lowest dose (0.25mg)
- Eat smaller, low-fat meals
- Stay hydrated
Qué hace
Sientes menos hambre, tu comida se digiere más lento, tu azúcar en sangre es más baja y pierdes peso poco a poco.
Cómo funciona
La semaglutida es como un termostato para el hambre. Le dice a tu cerebro que estás lleno y le indica a tu estómago que se vacíe despacio.
Enciende los interruptores GLP-1 en tu páncreas, cerebro e intestino. Esto controla tu azúcar en sangre y tu hambre.
Qué esperar
Notarás menos hambre en pocos días. Perderás mucho peso a las 8-12 semanas.
- Semana 1: Sientes menos hambre. Podrías sentir un poco de náuseas.
- Semanas 2-4: La dosis sube lentamente. Sigues perdiendo peso.
- Semanas 8-12: Sigues perdiendo peso y tu azúcar en sangre mejora.
Bueno saber
- Comienza con la dosis más pequeña (0,25 mg)
- Come porciones más pequeñas con menos grasa
- Bebe mucha agua
Manteniéndose seguro
- Sentirse con náuseas (hasta 40%)
- Vómitos
- Diarrea
- Estreñimiento (dificultad para ir al baño)
Evitar si tienes:
- Personas que o cuya familia tuvo cierto tipo de cáncer de tiroides
- Personas con una condición llamada síndrome MEN-2
- Personas que están embarazadas o en período de lactancia
Mecanismo de acción
Agonista del receptor GLP-1 que estimula la secreción de insulina, reduce el glucagón y retrasa el vaciamiento gástrico.
Activa los receptores GLP-1 en el páncreas, el cerebro y el intestino para regular la glucosa y el hambre.
Farmacodinamia
Supresión del apetito en pocos días; pérdida de peso significativa a las 8-12 semanas.
Menor hambre, digestión más lenta, niveles más bajos de azúcar en sangre, pérdida de peso progresiva.
Cronología
- Semana 1: Reducción inicial del apetito y posible náusea leve.
- Semanas 2-4: Aumento gradual de la dosis y pérdida de peso continua.
- Semanas 8-12: Pérdida de peso progresiva y mejora glucémica.
Comparaciones
- Semaglutida — efectividad Muy Alta, seguridad Buena, costo $$$, Fácil de usar
- Tirzepatida — efectividad Muy Alta, seguridad Buena, costo $$$, Fácil de usar
Efectos adversos
Comunes:
- Náuseas (hasta 40%)
- Vómitos
- Diarrea
- Estreñimiento
Raros:
- Pancreatitis
- Enfermedad de la vesícula biliar
- Reacción alérgica grave
Contraindicaciones y mitigación de riesgos
Contraindicado en:
- Antecedentes personales/familiares de carcinoma medular de tiroides
- Síndrome MEN-2
- Embarazo o lactancia
- Comenzar con la dosis más baja (0,25 mg)
- Consumir comidas más pequeñas y bajas en grasa
- Mantenerse hidratado
Reference data
Specifications
- Molecular formula
- C187H291N45O59
- Molecular weight
- 4113.6 g/mol
- Half-life
- ~7 days
- Route
- Subcutaneous
- Cycle length
- Ongoing (approved for chronic use); titration over 16-20 weeks
- Storage
- Unopened: refrigerate at 2-8 C. After first use: room temperature (up to 30 C) for up to 56 days. Do not freeze.
- Legal status
- FDA-approved: Ozempic (T2D, 2017), Wegovy (obesity, 2021), Rybelsus (oral T2D, 2019). Prescription required.
FAQ
Common questions
Is semaglutide FDA-approved for weight loss?
Yes, under brand names Ozempic (diabetes) and Wegovy (weight loss).
What are common side effects?
Nausea, vomiting, diarrhea, and constipation occur in ≥5% of patients.
What is the evidence level?
This compound is classified as Clinical evidence. Randomized controlled trial data in humans exists and supports use in specific contexts.
Research
Research & sources
Current evidence for Semaglutide is rated as Clinical evidence. Human clinical evidence supports the reported effects.
- 1. Semaglutide for weight loss (2021) — DOI:10.1056/NEJMoa2032183
- 2. GLP-1 receptor agonists (2019) — DOI:10.2337/dci19-0034
- 3. Wilding et al. — Semaglutide 2.4 mg for obesity (STEP 1 trial)
- 4. Marso et al. — Semaglutide cardiovascular outcomes (SUSTAIN-6)
- 5. Rubino et al. — STEP 4 trial: sustained weight loss