GLP-1 Medications

The following GLP-1 Medications are FDA approved for weight loss.
Liraglutide
Semaglutide
Tirzepatide

GLP-1 receptor agonists, or glucagon-like peptide-1 receptor agonists. It increases insulin secretion, which is good for diabetes. But at higher doses, it acts on centers in the brain and suppresses appetite. It is important for patients to use this medication in conjunction with lifestyle intervention. What this medicine does is help patients adhere to a reduced-calorie diet. With obesity, you always need lifestyle changes plus the medicine.

Liraglutide and Semaglutide are GLP-1 Medications:

Liraglutide is indicated for chronic weight management in adults with a BMI of 27 kg/m² or greater who have at least one weight-related comorbidity, such as type 2 diabetes or hypertension, or in adults with a BMI of at least 30 kg/m². It is NOT indicated for those with Type 1 diabetes.

Semaglutide is indicated for chronic weight management in adults with a BMI of 27 kg/m² or greater who have at least one weight-related comorbidity, such as type 2 diabetes or hypertension, or in adults with a BMI of at least 30 kg/m². It is NOT indicated for those with Type 1 diabetes.

Semaglutide Contraindications, Warnings Precautions

Contraindications

  • Personal or family history of medullary thyroid carcinoma or in patients with Multiple Endocrine Neoplasia syndrome type 2.

  • Known hypersensitivity to semaglutide. 

 

Semaglutide Warnings and Precautions

  • Thyroid C-cell Tumors: See Boxed Warning.

  • Acute Pancreatitis: Has occurred in clinical trials. Discontinue promptly if pancreatitis is suspected. Do not restart if pancreatitis is confirmed.

  • Acute Gallbladder Disease: Has occurred in clinical trials. If cholelithiasis is suspected, gallbladder studies and clinical follow-up are indicated.

  • Hypoglycemia: Concomitant use with an insulin secretagogue or insulin may increase the risk of hypoglycemia, including severe hypoglycemia. Reducing the dose of insulin secretagogue or insulin may be necessary.

  • Acute Kidney Injury: Has occurred. Monitor renal function when initiating or escalating doses of WEGOVY if experiencing severe adverse gastrointestinal reactions or with renal impairment and experiencing severe adverse gastrointestinal reactions.

  • Hypersensitivity: Anaphylactic reactions and angioedema have been reported postmarketing. Discontinue WEGOVY if suspected and promptly seek medical advice.

  • Diabetic Retinopathy Complications in Patients with Type 2 Diabetes: Has been reported in trials with semaglutide. Patients with a history of diabetic retinopathy should be monitored.

  • Heart Rate Increase: Monitor heart rate at regular intervals.

  • Suicidal Behavior and Ideation: Monitor for depression or suicidal thoughts. Discontinue WEGOVY if symptoms develop. 

 

 Semaglutide Warnings: Risk of Thyroid C-Cell Tumors

  • See full prescribing information for complete boxed warning.

  • In rodents, semaglutide causes thyroid C-cell tumors at clinically relevant exposures. It is unknown whether WEGOVY causes thyroid C-cell tumors, including medullary thyroid carcinoma (MTC), in humans as the human relevance of semaglutide-induced rodent thyroid C-cell tumors has not been determined.

  • WEGOVY is contraindicated in patients with a personal or family history of MTC or in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).

Tirzepatide is a once-weekly GIP (glucose-dependent insulinotropic polypeptide) receptor and GLP-1 (glucagon-like peptide-1) receptor agonist. Tirzepatide is a single novel molecule that activates the body's receptors for GIP and GLP-1, which are natural incretin hormones. GIP is a hormone that may complement the effects of GLP-1 receptor agonism. GIP has been shown to decrease food intake while blunting the metabolic adaptive responses that usually occur with calorie restriction resulting in weight reductions, and when combined with GLP-1 receptor agonism, may result in greater effects on markers of metabolic dysregulation such as body weight, glucose and lipids. 

Tirzepatide exerts its pharmacological effects through dual agonism of the glucagon-like peptide-1 receptor (GLP-1R) and the glucose-dependent insulinotropic polypeptide receptor (GIPR). This unique mechanism of action sets it apart from other antidiabetic medications.

Tirzepatide is a GIP and GLP-1 receptor agonist, so its mechanism of action is it activates both GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1) hormone receptors.

Tirzepatide Contraindications

  • Tirzepatide is contraindicated in patients with a personal or family history of MTC or in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). Symptoms of thyroid tumors (e.g., a mass in the neck, dysphagia, dyspnea, persistent hoarseness). Routine monitoring of serum calcitonin or using thyroid ultrasound is of uncertain value for early detection of MTC in patients treated with Zepbound™.

 

Tirzepatide Warnings/Precautions & Drug Interactions

Risk of Thyroid C-Cell Tumors

In rats, tirzepatide caused a dose-dependent and treatment-duration-dependent increase in the incidence of thyroid C-cell tumors (adenomas and carcinomas) in a 2-year study at clinically relevant plasma exposures. Human relevance of tirzepatide-induced rodent thyroid C-cell tumors has not been determined.

Tirzepatide is contraindicated in patients with a personal or family history of MTC or in patients with MEN 2. There is a potential risk for MTC with the use of Tirzepatide. Symptoms of thyroid tumors (e.g., a mass in the neck, dysphagia, dyspnea, persistent hoarseness).

Patients with thyroid nodules noted on physical examination or neck imaging should be further evaluated.

Severe Gastrointestinal Disease

Use of Tirzepatide has been associated with gastrointestinal adverse reactions, sometimes severe. In clinical trials, severe gastrointestinal adverse reactions were reported more frequently among patients receiving Tirzepatide (5 mg 1.7%, 10 mg 2.5%, 15 mg 3.1%) than placebo (1%).  Tirzepatid has not been studied in patients with severe gastrointestinal disease, including severe gastroparesis, and is therefore not recommended in these patients.