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Semaglutide

FDA Approved

GLP-1 Receptor Agonist | Weight Loss & Diabetes

Dose 0.25mg starting, titrate to 1-2.4mg weekly
Frequency Once weekly (same day each week)
Cycle Ongoing therapy as prescribed
Storage Pen: 2-8°C before first use, room temp up to 56 days after. Compounded: 2-8°C
Accumulation Plotter

Long-acting GLP-1 receptor agonist approved for type 2 diabetes and chronic weight management. Over 17,000 trial participants have demonstrated significant efficacy through appetite suppression and glycemic control. The 7-day half-life enables convenient weekly dosing.

Mechanism of Action

Mimics native GLP-1, binding to receptors to stimulate glucose-dependent insulin secretion, suppress glucagon, slow gastric emptying, and reduce appetite via hypothalamic pathways.

Key Benefits

  • 15-20% average body weight reduction
  • Established cardiovascular protection
  • Convenient once-weekly dosing options
  • Comprehensive safety data from extensive trials
  • Flexible injectable and oral formulations
Molecular Weight
4,113.64 Da
Chain Length
31 amino acids
Type
GLP-1 receptor agonist
Amino Acid Sequence
One-letter: HUEGTFTSDVSSYLEGQAAKEFIAWLVRGRG
H₂N
H 1
O ‖ C
N
U 2
O ‖ C
N
E 3
O ‖ C
N
H
G 4
O ‖ C
N
T 5
O ‖ C
N
F 6
O ‖ C
N
T 7
O ‖ C
N
S 8
O ‖ C
N
D 9
O ‖ C
N
V 10
O ‖ C
N
S 11
O ‖ C
N
S 12
O ‖ C
N
Y 13
O ‖ C
N
L 14
O ‖ C
N
E 15
O ‖ C
N
H
G 16
O ‖ C
N
Q 17
O ‖ C
N
A 18
O ‖ C
N
A 19
O ‖ C
N
K 20
O ‖ C
N
E 21
O ‖ C
N
F 22
O ‖ C
N
I 23
O ‖ C
N
A 24
O ‖ C
N
W 25
O ‖ C
N
L 26
O ‖ C
N
V 27
O ‖ C
N
R 28
O ‖ C
N
H
G 29
O ‖ C
N
R 30
O ‖ C
N
H
G 31
COOH
His
1

Histidine

Position 1

Aib
2

Aminoisobutyric Acid

Position 2

Glu
3

Glutamic Acid

Position 3

Gly
4

Glycine

Position 4

Thr
5

Threonine

Position 5

Phe
6

Phenylalanine

Position 6

Thr
7

Threonine

Position 7

Ser
8

Serine

Position 8

Asp
9

Aspartic Acid

Position 9

Val
10

Valine

Position 10

Ser
11

Serine

Position 11

Ser
12

Serine

Position 12

Tyr
13

Tyrosine

Position 13

Leu
14

Leucine

Position 14

Glu
15

Glutamic Acid

Position 15

Gly
16

Glycine

Position 16

Gln
17

Glutamine

Position 17

Ala
18

Alanine

Position 18

Ala
19

Alanine

Position 19

Lys
20

Lysine

Position 20

Glu
21

Glutamic Acid

Position 21

Phe
22

Phenylalanine

Position 22

Ile
23

Isoleucine

Position 23

Ala
24

Alanine

Position 24

Trp
25

Tryptophan

Position 25

Leu
26

Leucine

Position 26

Val
27

Valine

Position 27

Arg
28

Arginine

Position 28

Gly
29

Glycine

Position 29

Arg
30

Arginine

Position 30

Gly
31

Glycine

Position 31

N-terminus C-terminus
Hydrophobic
Polar
Positive (+)
Negative (-)
Modified

Weight Loss

  • Clinically Significant Weight Reduction

    FDA-approved for chronic weight management with average 15-20% body weight loss in clinical trials.

  • Appetite and Craving Control

    Reduces hunger and food cravings through central nervous system GLP-1 receptor activation.

  • Sustained Weight Maintenance

    Long-term studies show maintained weight loss with continued treatment over 2+ years.

Diabetes

  • Glycemic Control

    FDA-approved for type 2 diabetes with HbA1c reductions of 1.5-2% in clinical trials.

  • Cardiovascular Protection

    Proven 26% reduction in cardiovascular death, MI, or stroke in high-risk diabetes patients.

  • Beta Cell Preservation

    Improves insulin secretion and may preserve pancreatic beta cell function.

Metabolic

  • Metabolic Syndrome Improvement

    Addresses multiple components: weight, glucose, blood pressure, and lipids.

  • NASH/Fatty Liver

    Emerging evidence for improvements in non-alcoholic fatty liver disease.

  • Inflammation Reduction

    Decreases systemic inflammation markers independent of weight loss.

Pre-filled pen devices for once-weekly subcutaneous injection. Brands include Ozempic (diabetes) and Wegovy (weight loss).

GoalDoseFrequencyRoute
Weight Loss Initiation0.25mgWeekly x 4 weeks, then increaseSubcutaneous
Weight Loss Maintenance2.4mgWeekly (after 16-week titration)Subcutaneous
Diabetes Management0.5-1mgWeeklySubcutaneous
Cardiovascular Protection0.5-1mgWeeklySubcutaneous
Tolerability-Based0.25-2.4mgWeekly (individualized)Subcutaneous

Reconstitution Instructions

Materials Needed:
  • Semaglutide pre-filled pen or vial
  • Pen needles (if using pen device)
  • Alcohol swabs
  • Sharps disposal container
  • Injection site rotation chart
  1. 1 If using pre-filled pen, attach new needle and prime per instructions
  2. 2 If using vial, draw prescribed dose with appropriate syringe
  3. 3 Clean injection site with alcohol swab and let dry
  4. 4 Inject subcutaneously at 90-degree angle (45-degree if lean)
  5. 5 Hold for 6 seconds after injection to ensure full dose delivery
  6. 6 Dispose of needle safely and rotate injection sites weekly
Insulin

May increase hypoglycemia risk when combined; requires blood glucose monitoring.

monitor
Tirzepatide

Both are incretin mimetics with overlapping mechanisms; concurrent use increases side effects.

avoid
Cagrilintide

Combined as CagriSema in clinical trials for enhanced weight loss efficacy.

synergistic
Metformin

Commonly used together for diabetes management with good safety profile.

compatible
BPC-157

No contraindications; may help with GI side effects.

compatible
Sulfonylureas

Increased hypoglycemia risk; may require sulfonylurea dose reduction.

monitor
Oral Medications

Delayed gastric emptying may affect absorption of oral medications.

requires timing
Week 1-4

Mild appetite reduction, possible nausea during initial dose

Month 2-3

Noticeable weight loss (5-10% typical), improved satiety

Month 4-6

Continued weight loss (10-15% common), stable glucose levels

Month 6+

Weight loss plateau possible, focus on maintenance

Diabetes

Blood sugar improvements within 1-2 weeks

Common Side Effects

  • Nausea
  • Diarrhea
  • Vomiting
  • Constipation
  • Abdominal pain

Stop Signs - Discontinue if:

  • Severe persistent abdominal pain (possible pancreatitis)
  • Persistent vomiting preventing fluid intake
  • Signs of thyroid tumor (neck lump, hoarseness, trouble swallowing)
  • Severe allergic reaction (rash, itching, difficulty breathing)
  • Vision changes (possible diabetic retinopathy progression)
  • Severe hypoglycemia (if combined with insulin/sulfonylureas)
  • Kidney problems (decreased urination, swelling)

Contraindications

  • Personal or family history of medullary thyroid cancer
  • Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
  • Pregnancy or breastfeeding
  • History of pancreatitis

Good Signs

  • FDA-approved branded products (Ozempic, Wegovy, Rybelsus)
  • Proper refrigeration verified and not expired
  • Clear, colorless to slightly yellow solution in pen/vial

Warning Signs

  • Compounded versions - FDA warns about untested compounded semaglutide

Bad Signs

  • Cloudy or discolored solution
  • Particles or precipitation visible
  • Non-pharmacy sources or unverified online sellers
  • STEP 1 Trial - Weight Management
    (2021)

    14.9% average weight loss versus 2.4% with placebo over 68 weeks with 2.4mg weekly.

  • SELECT Cardiovascular Outcomes
    (2023)

    20% reduction in major adverse cardiovascular events over 5 years with 2.4mg weekly.

  • SUSTAIN Diabetes Program
    (2016-2019)

    Average HbA1c reductions of 1.5-1.8% across multiple trials.

  • STEP 5 Two-Year Maintenance
    (2022)

    Sustained weight loss of 15.2% at week 104 with 2.4mg weekly.

  • PIONEER Oral Semaglutide
    (2019)

    Oral efficacy comparable to injectable formulations at 3-14mg daily.

  • STEP TEENS Adolescent Study
    (2022)

    16.1% BMI reduction in adolescent population over 68 weeks.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.