Semaglutide is a medication prescribed for the management of certain long-term health conditions. It belongs to a class of compounds known as glucagon-like peptide-1 (GLP-1) receptor agonists. The official prescribing information, often referred to as the drug label, details the drug’s biological function, approved applications, administration protocols, and associated risks. Understanding the contents of this label is important, as it represents the comprehensive data reviewed by regulatory authorities.
Understanding Semaglutide’s Action
Semaglutide works by mimicking the action of a natural hormone in the body called glucagon-like peptide-1 (GLP-1), which is released in response to eating a meal. By binding to and activating the GLP-1 receptors, the medication exerts its effects on several physiological systems involved in metabolism. One primary action is its glucose-dependent effect on the pancreas, stimulating the release of insulin when blood sugar levels are elevated. This mechanism helps to improve glycemic control in people with Type 2 Diabetes Mellitus (T2DM) by lowering circulating glucose.
The drug also helps to suppress the secretion of glucagon, a hormone that signals the liver to release stored glucose, particularly after a meal. Furthermore, semaglutide is known to slow down gastric emptying, meaning food remains in the stomach for a longer period of time. This delayed movement contributes to increased feelings of satiety, or fullness, which helps to reduce overall calorie intake.
Approved Therapeutic Indications
The official label identifies specific patient populations and conditions for which semaglutide has received regulatory approval. One primary indication is to improve blood sugar control in adults diagnosed with Type 2 Diabetes Mellitus, used alongside diet and exercise interventions. For patients with T2DM who also have established cardiovascular disease, the drug is also indicated to reduce the risk of major adverse cardiovascular events, such as heart attack or stroke.
The medication is also approved for chronic weight management in adults. This includes individuals with obesity, defined as a body mass index (BMI) of 30 kg/m² or greater, or those categorized as overweight (BMI of 27 kg/m² or greater) who have at least one weight-related condition. These weight-related conditions include high blood pressure, dyslipidemia, or T2DM. Using the medication for purposes outside of these defined indications, such as solely for cosmetic weight loss, is considered an off-label application.
Administration Protocols and Dosage Escalation
Semaglutide is administered via a once-weekly subcutaneous injection using a pre-filled pen device. The injection site can be the abdomen, thigh, or upper arm. It must be given on the same day each week, independent of meal timing.
The official label mandates a slow, gradual increase in dosage, known as titration, which is designed to enhance patient tolerability and reduce gastrointestinal side effects. Titration typically begins with a low starting dose, such as 0.25 milligrams (mg) once weekly. The dose is systematically increased every four weeks through intermediate steps (e.g., 0.5 mg, 1.0 mg, 1.7 mg) until the target maintenance dose is reached. For chronic weight management, the full maintenance dose is 2.4 mg once weekly, usually reached after about 16 weeks of gradual escalation.
Critical Warnings and Contraindications
The official prescribing information contains a prominent Boxed Warning, the strongest caution issued by regulatory agencies, concerning the risk of thyroid C-cell tumors. This warning is based on findings from studies in rodents, where semaglutide caused dose- and time-dependent increases in these tumors. Although it is currently unknown whether the medication causes this specific type of cancer in humans, the caution remains due to the potential risk.
Semaglutide is strictly contraindicated for patients with a personal or family history of Medullary Thyroid Carcinoma (MTC), which is a rare form of thyroid cancer. It is also contraindicated for individuals with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2), a genetic condition that predisposes a person to MTC. Beyond this primary warning, the label includes cautions about other serious potential health issues that require immediate medical attention.
Serious adverse events include the risk of acute pancreatitis, characterized by severe, persistent abdominal pain that may radiate to the back. There is also a noted risk for complications in patients with a history of diabetic retinopathy, as rapid improvements in blood sugar control can sometimes temporarily worsen existing eye conditions. Furthermore, the label warns about the potential for acute gallbladder disease, including gallstones, and acute kidney injury, often resulting from dehydration due to severe gastrointestinal upset.
Common and Expected Adverse Reactions
The label details the common adverse reactions patients are most likely to experience. The most frequently reported side effects are concentrated in the gastrointestinal tract, resulting directly from the medication’s mechanism of slowing digestion. These common effects include:
- Nausea
- Vomiting
- Diarrhea
- Constipation
- General abdominal pain or discomfort
Nausea was the most prevalent complaint in clinical trials, particularly during the initial phase of treatment. These gastrointestinal issues are often transient, decreasing in frequency and severity as the body adapts to the medication over several weeks. Other expected reactions include headache, fatigue, and dyspepsia (indigestion).