Semaglutide: Uses, Weight Loss, How to Take & Side Effects

Semaglutide is an antidiabetic that is indicated for the treatment of type 2 diabetes. It works by stimulating insulin production in the pancreas and decreasing glucagon production, which helps to reduce blood glucose levels in the blood. It is most effective when combined with a healthy diet and regular exercise.

This medication is also used for weight loss. It promotes satiety and decreases the sensation of hunger. As a result, weight loss occurs due to a reduction of overall daily calorie intake.

Semaglutide can be obtained with a prescription at pharmacies as an injectable (also known as Ozempic) or as pills (also known as Rybelsus). It should be used as prescribed by your family doctor or endocrinologist. 

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Approved uses in the United States

Semaglutide is approved in the United States for several conditions related to blood sugar control, weight management, cardiovascular protection, kidney disease progression, and metabolic liver disease. Its approved uses vary according to the formulation prescribed.

1. Type 2 diabetes

Semaglutide is approved to improve glycemic control in adults with type 2 diabetes when used alongside diet and exercise.

Both injectable semaglutide (Ozempic) and oral semaglutide (Rybelsus) help lower HbA1c by stimulating insulin secretion in a glucose-dependent way, reducing glucagon levels, delaying gastric emptying, and decreasing appetite.

Injectable semaglutide has also been approved to reduce the risk of major cardiovascular events, and to reduce the risk of kidney disease worsening in adults with type 2 diabetes and chronic kidney disease.

2. Weight management and obesity

Injectable semaglutide 2.4 mg (Wegovy) is approved for chronic weight management in adults with a BMI of 30 kg/m² or higher, or in adults with a BMI of 27 kg/m² or higher who also have a weight-related condition, such as high blood pressure, type 2 diabetes, or high cholesterol.

It is also approved for obesity management in adolescents over 12 years of age who weigh more than 60 kg.

Semaglutide helps regulate appetite and calorie intake, which can support sustained weight loss when used together with a reduced-calorie diet and regular physical activity.

3. Emerging and expanded uses

Semaglutide has received additional approvals in the United States to lower the risk of cardiovascular death, non-fatal heart attack, and non-fatal stroke in adults with established cardiovascular disease who also have overweight or obesity.

It is also approved to slow the progression of chronic kidney disease in adults with type 2 diabetes.

More recently, semaglutide 2.4 mg received accelerated approval for the treatment of metabolic dysfunction-associated steatohepatitis (MASH) in adults with moderate-to-advanced fibrosis, based on evidence showing improvements in liver inflammation and fibrosis.

Available forms

Semaglutide is available in the United States in three different forms, each with its own dosing schedule and intended use. Although all forms work through the same GLP-1 mechanism, they differ in how they are taken, how quickly they act, and which conditions they are approved to treat.

1. Ozempic (injectable semaglutide)

Ozempic is a once-weekly injectable form used mainly to treat type 2 diabetes and reduce cardiovascular and kidney risks. It delivers semaglutide through a subcutaneous pen, allowing steady blood levels and effective glucose control.

2. Rybelsus (oral semaglutide)

Rybelsus is the only oral form of semaglutide and is taken once daily. It must be taken on an empty stomach with a small amount of water, offering an alternative for people who prefer not to use injections.

3. Wegovy (injectable semaglutide)

Wegovy is a once-weekly injectable form specifically approved for chronic weight management in adults and adolescents. It is given at higher doses than Ozempic and follows a gradual titration schedule to improve gastrointestinal tolerance.

Dosage and administration

The dosing of semaglutide varies according to the formulation prescribed and the condition being treated. The table below outlines the typical schedules used in the United States.

Formulation Starting Dose Maintenance Dose Frequency Key Instructions
Ozempic (injectable semaglutide) 0.25 mg once weekly for the first 4 weeks 0.5 mg once weekly; may increase to 1 mg or 2 mg if additional blood sugar control is needed Once weekly Inject subcutaneously in the belly, thigh, or upper arm. Use on the same day each week. Dose increases should occur only after at least 4 weeks at the prior dose.
Rybelsus (oral semaglutide) 3 mg once daily for 30 days 7 mg once daily; may increase to 14 mg once daily if needed Daily Take on an empty stomach with no more than 4 oz of water. Wait at least 30 minutes before eating, drinking, or taking other medications. Tablets must be swallowed whole.
Wegovy (injectable semaglutide) 0.25 mg once weekly for weeks 1–4 Gradual increases each month until reaching 2.4 mg once weekly (0.5 mg in weeks 5–8, 1 mg in weeks 9–12, 1.7 mg in weeks 13–16, then 2.4 mg onward) Once weekly Inject subcutaneously in the belly, thigh, or upper arm. Follow the 16-week titration schedule to reduce gastrointestinal side effects. Use on the same day each week. If a dose is missed for more than 2 weeks, consult a healthcare provider about restarting.

Possible side effects

The most common side effects of using semaglutide are:

  • Nausea or vomiting
  • Stomach ache
  • Heartburn or poor digestion
  • Diarrhea or constipation
  • Excess intestinal gas
  • Frequent burping
  • Loss of appetite
  • Difficulty swallowing
  • Hypoglycemia
  • Anxiety or depression
  • Headache
  • Dizziness
  • Tiredness

It is important to seek immediate medical attention or to proceed to the nearest emergency room if you experience symptoms such as decreased urine output, severe nausea and vomiting that does not improve, severe stomach or abdominal pain, blurred vision, hoarseness, shortness of breath, heartbeat rapid heartbeat, yellowing of the skin or eyes, swelling, and watery or bloody diarrhea.

In addition, the doctor should be informed if you notice changes in mood or behavior, depression, anxiety, talks or thinks about hurting themselves or thoughts about suicide.

Semaglutide can also cause less common effects, such as inflammation of the pancreas (pancreatitis), gallstones, changes in the taste of food and stomach paralysis (gastroparesis).

Injections may cause side effects may appear at the injection site, such as pain, itching, irritation, lesions and purple spots near the place semaglutide was applied.

Ozempic face

Ozempic face is a term that has been popularly used to indicate the changes that rapid weight loss can cause to the face, such as facial aging or sagging.

However, this term is not a medical term, as any procedure that leads to rapid weight loss, such as bariatric surgery, can have the same effect on the face. Furthermore, the term Ozempic face appears to reinforce the stigma surrounding the treatment of obesity, which is why using this term is not recommended.

Contraindications for use

Semaglutide should not be used by patients who are allergic to any of the formula's components nor by people with type 1 diabetes or diabetic ketoacidosis.

This medicine should also not be used by children and adolescents under 18 years of age, nor by pregnant or breastfeeding women.

In addition, people with kidney or pancreatic disease, people with stomach problems such as hiatal hernias or GERD, or people who are using other medication  should inform their doctor about these conditions before starting semaglutide.

Care during treatment

Be sure to keep the following considerations in mind when taking semaglutide:

  • Do not use semaglutide unless prescribed by your doctor.
  • Take or inject semaglutide at the right times, as advised by your doctor.
  • Do not increase the dose on your own, and only increase as prescribed.
  • Inform your doctor of all medications you use, including vitamins or dietary supplements, as semaglutide may interfere with the absorption of these medications.
  • Follow the diet and exercise advice recommended by your doctor.
  • Eat in small quantities with short intervals in between.
  • Drink at least 2 L of water per day, to keep the body hydrated, and to avoid dehydration in the case of diarrhea or vomiting.
  • Avoid very hot foods, as the steam from the food can cause nausea and vomiting.
  • Avoid consuming alcoholic beverages.
  • Tell your doctor immediately if you become pregnant during treatment.

In addition, medical follow-ups should be carried out regularly. You should communicate any side effects to your doctor so that treatment can be reevaluated. 

Read more about the weight loss diet that you can maintain when taking semaglutide.