How does Wegovy work for weight loss?

At a high level, Wegovy (semaglutide) works by increasing feelings of fullness. As a result, people taking the weight loss medication tend to eat fewer calories.

Wegovy increases feelings of fullness. Feeling full sooner and longer can lead to eating less and losing weight. Here is how Wegovy works for weight loss.

The active ingredient in Wegovy is called semaglutide. Semaglutide works by mimicking GLP-1, a hormone that regulates appetite and satiety, or fullness. 

GLP-1 receptor agonists such as Wegovy activate the receptor that the naturally occurring hormone binds to. This triggers a cascade of responses in the brain and throughout the body after eating, including:

• Slowing how quickly food leaves the stomach,, which helps people feel full sooner and longer

• Regulating blood sugar levels after meals, which may also help reduce hunger and cravings.

• Sending fullness signals to the brain, prompting eating to stop sooner

• Helping the brain feel less focused on food, which may reduce "food noise" and cravings

See if you qualify

The effects of Wegovy begin almost immediately after starting the medication, but it can take about a month to notice weight changes, whether using injectable or oral Wegovy. In clinical trials, people lost about 2% of their body weight in the first month of taking the Wegovy pill or injection.

In one study, people on injectable Wegovy lost approximately  2% within the first month of treatment. By comparison, people on a placebo lost less than 1%. Both groups also made lifestyle changes such as adjusting eating habits and increasing exercise.

As the trial went on, the gap between the subjects receiving a placebo and those receiving Wegovy continued to grow. After 68 weeks (about a year and four months), the participants taking semaglutide (the active ingredient in Wegovy) lost nearly 15% of their body weight on average, compared with less than 3% in the placebo group.

In addition to losing a significant amount of weight, those taking semaglutide also experienced other improvements in their cardiometabolic health and reported better physical function.

The Wegovy pill produces similar — albeit slightly less — weight loss results to injectable Wegovy. In a 64-week clinical trial, people lost 13.6% of their starting body weight on the Wegovy pill. Those taking a placebo, on the other hand, lost only 2.2% of their body weight.

Wegovy's side effects are typically gastrointestinal and range from mild to moderate. Nausea, diarrhea, vomiting, and constipation are the most common side effects of the Wegovy pill and injection, often lessening over time as use of the medication continues. Additional side effects of Wegovy may include:

• Abdominal pain

• Headache

• Fatigue

• Heartburn/indigestion

• Dizziness

• Bloating

• Burping/flatulence

• Gastroesophageal reflux disease (GERD)

Severe side effects of Wegovy

Severe side effects of Wegovy may include allergic reactions, gallbladder disorders, pancreatitis (inflammation of the pancreas),acute  kidney injury, increased heart rate, and pulmonary aspiration during anesthesia or deep sedation. In people with type 2 diabetes, Wegovy may also increase the risk of hypoglycemia (low blood sugar), especially when used with insulin or certain other diabetes medications, and diabetic retinopathy complications.

People experiencing severe side effects of Wegovy should seek emergency medical attention.

Wegovy warnings

Wegovy carries a boxed warning from the US Food and Drug Administration (FDA): animal studies found that semaglutide increases the risk of thyroid tumors in rodents. It is not known whether this occurs in humans, but Wegovy is not recommended for people with multiple endocrine neoplasia syndrome type 2 or a personal or family history of medullary thyroid carcinoma, a type of thyroid cancer.

Wegovy is not appropriate for everyone. It should not be used with other GLP-1 receptor agonists, such as Ozempic (semaglutide), and a healthcare provider can give advice  about combining Wegovy with other weight loss medications or supplements. Wegovy should not be used during pregnancy and should be stopped at least 2 months before a planned pregnancy.

Before using Wegovy, people should tell their healthcare provider about their personal and family medical history and any medications they are currently taking.

Wegovy is FDA-approved for people with obesity (defined as having a body mass index, BMI, of 30 or higher) or those who have overweight (a BMI of 27 or higher) along with a weight-related health condition, such as type 2 diabetes, high blood pressure, or high cholesterol. 

Some healthcare providers may prescribe Wegovy for weight loss even if a person does not precisely meet these BMI or comorbidity criteria, using their clinical judgment to determine if Wegovy is appropriate for that person. 

Wegovy may also be prescribed to lower the risk of stroke, heart attack, and death in people with heart disease and obesity or overweight. Additionally, the Wegovy injection is approved for adults with noncirrhotic MASH with moderate-to-advanced liver fibrosis.

The Wegovy tablet is taken daily in the morning on an empty stomach, while the injection is given weekly, with or without food. Here is more information on how to administer a dose of Wegovy.

• The Wegovy injection should be administered once a week, on the same day each week either with or without meals. Wegovy is injected subcutaneously (under the skin) into the abdomen, upper arm, or thigh using the attached needle on the pen.

• The Wegovy pill should be swallowed whole in the morning on an empty stomach, with 4 ounces of water or less. The dose should be taken at least 30 minutes before drinking anything else, eating food, or taking other medications.

Available doses of Wegovy: The Wegovy injection comes in six doses: 0.25 mg, 0.5 mg, 1 mg, 1.7 mg, 2.4 mg, and 7.2 mg. The Wegovy pill comes in four doses: 1.5 mg, 4 mg, 9 mg, and 25 mg.

Storage instructions for Wegovy: When not in use, Wegovy pens should be stored in the refrigerator. Oral Wegovy should be stored at room temperature in its original bottle, away from moisture and light.

Check for free

The list price for Wegovy is $1,349.02 per month. Price depends on many factors, including insurance coverage, dosage, and pharmacy.

If your insurance plan does not cover Wegovy, or if you pay cash for your prescriptions, Wegovy may cost less on Ro. Just keep in mind that cash-pay prices for Wegovy vary by dose and form. Here’s how much Wegovy costs via self-pay on Ro*: 

• Wegovy pill : $149–$299 per month, depending on the dose.

• Wegovy injection: $199–$399 per month, depending on the dose. 

For people who fill their prescription at a pharmacy without insurance, the price could be as high as the list price of $1,349.02. However, Wegovy coupons and pharmacy discounts may lower the price.

With the Wegovy savings card, eligible patients can pay as low as $25 per month. To qualify for this savings program, patients need a commercial health insurance plan with coverage for Wegovy. People with state, federal, or government-funded insurance, such as Medicare or Medicaid, are not eligible.

*Terms and restrictions may apply for certain cash-pay prices

For some people, lifestyle changes like healthy eating habits and exercise alone may not be enough to meet their weight and overall  health goals. Talking with a healthcare provider is the best way to find out if Wegovy could be a fit.

• Wegovy works by increasing feelings of fullness. The medication mimics the body's natural GLP-1 hormone to slow down digestion, boost feelings of fullness, help regulate blood sugar levels, and reduce cravings and appetite.

• People may be eligible for Wegovy for different health reasons, including weight management, lowering the risk of serious heart problems, or treating a specific form of fatty liver disease with the injection.When prescribed for weight loss, Wegovy is FDA-approved for people with a BMI of 30 or higher (obesity) or a BMI of 27 or higher (overweight) with a weight-related health condition such as type 2 diabetes or high cholesterol.

• Wegovy is also indicated for certain heart and liver conditions. It can lower the risk of serious heart problems in certain adults with heart disease and obesity or overweight. The injection is also approved to treat a specific form of fatty liver disease.

• Wegovy is available as a pill or injection. The pill is taken daily in the morning on an empty stomach, at least 30 minutes before food, other  drinks, or other medications. The injection is taken weekly on the same day each week, with or without food.

• People may lose about 2% of their body weight in the first month of taking Wegovy. After a year and change, they lose about 13% of their starting body weight on the pill, and 15% on the injection.

• Gastrointestinal side effects are usually worse when starting Wegovy or increasing your dose. Due to the drug’s effects on the digestive system, side effects are often gastrointestinal, such as nausea, vomiting, or diarrhea.