Semaglutide injection (Wegovy®) is a glucagon-like peptide-1 (GLP-1) receptor agonist that is given as a once-weekly subcutaneous injection for “chronic weight management” in specified subgroups of patients (see FDA indications below).
Optional to read: Semaglutide was approved by the FDA in 2021 and was the first weight-loss medication to be approved since 2014.
On this page, we will provide basic information about this medication. Links to other articles on this website with more advanced information and tips related to this medication and related topics are provided below, under Related Pages.
FDA indications
According to the Prescribing Information, the wording of the FDA indications for semaglutide injection (Wegovy®) is as follows (the emphasis below in red has been added by us):
“WEGOVY is a glucagon-like peptide-1 (GLP-1) receptor agonist indicated in combination with a reduced calorie diet and increased physical activity:
• to reduce the risk of major adverse cardiovascular events (cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke) in adults with established cardiovascular disease and either obesity or overweight.
• to reduce excess body weight and maintain weight reduction long term in:
o Adults and pediatric patients aged 12 years and older with obesity
o Adults with overweight in the presence of at least one weight-related comorbid condition”
For more on the use of semaglutide injection (Wegovy®) to treat obesity and overweight, please see the following article on this website:
Semaglutide injection (Wegovy®) for weight loss in obesity and overweight
Mechanism of Action/ Pharmacodynamics
Semaglutide belongs to a group of medications called glucagon-like peptide-1 (GLP-1) agonists. GLP-1 is involved in the regulation of appetite and food intake.
For more on what GLP-1 is and an overview of other GLP-1 agonists, please see the following article on this website:
A simple primer on what GLP-1 agonists are
Relatively common side effects
In clinical trials, side effects that occurred on semaglutide injection (Wegovy®) with at least a 2% drug-placebo difference were:
1. Gastrointestinal:
All kinds of gastrointestinal side effects can occur (in decreasing order of incidence)—Nausea (28%), vomiting (18%), diarrhea (14%, close to twice as often on medication as on placebo), constipation (13%), abdominal pain (10%), dyspepsia (indigestion; 6%), eructation (belching; 6%), gastritis (2%).
2. Fatigue (6%)
3. Dizziness (4%)
4. Hypoglycemia in patients with type 2 diabetes (4%)
5. Hair loss (3%)
For more about the relatively common side effects of semaglutide injection (Wegovy®), please see the following article on this website:
Semaglutide injection (Wegovy®): Side effects
Boxed warning
Other potential serious side effects (Warnings and Precautions)
Semaglutide injection (Wegovy™) comes with the following nine “Warnings and Precautions” , which are worded exactly as in the official Prescribing Information:
1. Thyroid C-cell tumors (boxed warning)
2. Acute pancreatitis
3. Acute gallbladder disease
4. Hypoglycemia
5. Acute kidney injury
6. Hypersensitivity
7. Diabetic retinopathy complications in patients with type 2 diabetes
8. Heart rate increase
9. Suicidal behavior and ideation
10. Delayed gastric emptying
For important points on these ten “Warnings and Precautions” about semaglutide injection (Wegovy™) and what we need to do about them, please see the following article on this website:
Semaglutide injection (Wegovy®): Serious side effects, warnings, and contraindications
Dosage and Administration
The medication dose must be increased gradually over 16 to 20 weeks to 2.4 mg once weekly to reduce gastrointestinal side effects.
Dosage forms and strengths
Wegovy™ is available as a single-use, prefilled syringe in 5 different strengths: 0.25 mg, 0.5 mg, 1 mg, 1.7 mg, and 2.4 mg.
Optional to read: In contrast, Ozempic® is available as prefilled syringes containing 2 mg, 4 mg, or 8 mg of semaglutide. But, these syringes are not for single use. They can be used to deliver specific doses of semaglutide until the medication in that syringe is used up, as follows:
– The syringe containing 2 mg can deliver either 0.25 mg or 0.5 mg at a time
– The syringe containing 4 mg delivers 1 mg at a time
– The syringe containing 8 mg delivers 2 mg at a time.
Important! This page does not provide all the information needed to prescribe this medication. Please refer to the full Prescribing Information (see link below) before prescribing this medication.
Related Pages
GLP-1 agonists
A simple primer on what GLP-1 agonists are
Semaglutide injection (Wegovy®) for weight loss in obesity and overweight
Semaglutide injection (Wegovy®): Side effects
Semaglutide injection (Wegovy®): Serious side effects, warnings, and contraindications
Semaglutide injection (Wegovy®): Basic information
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References
Wegovy® Prescribing Information
Taha MB, Yahya T, Satish P, Laird R, Agatston AS, Cainzos-Achirica M, Patel KV, Nasir K. Glucagon-Like Peptide 1 Receptor Agonists: A Medication for Obesity Management. Curr Atheroscler Rep. 2022 May 28. doi: 10.1007/s11883-022-01041-7. Epub ahead of print. PMID: 35624390.
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