What is Rybelsus and how does it work for weight loss?

A GLP-1 that doesn’t involve needles and is as easy to take as a baby aspirin? Sounds great. But how does Rybelsus® work? We’ll explain. 

What is Rybelsus? 

Rybelsus (oral semaglutide) is a brand-name prescription medication taken daily to lower blood sugar levels and improve blood sugar control in adults with type 2 diabetes. It’s also the first FDA-approved GLP-1 receptor agonist that can be taken as an oral tablet instead of an injection. 

Made by Novo Nordisk, it’s FDA-approved as a treatment for type 2 diabetes, along with diet and exercise, and it’s also prescribed off-label for weight loss. Rybelsus contains semaglutide, the same active ingredient in popular injectable drugs Wegovy® (for weight loss) and Ozempic® (for type 2 diabetes).

How does Rybelsus work? 

The semaglutide in Rybelsus mimics a naturally occurring gut hormone GLP-1 (glucagon-like peptide 1), which triggers the GLP-1 receptors in the body to:  

• Prompt the pancreas to produce more insulin when blood sugar is high.
• Keep the liver from making and releasing too much sugar.
• Slow gastric emptying (the movement of food out of the stomach).

In a clinical trial, it improved glycemic (blood sugar) control, as measured by hemoglobin A1C levels, in adults with type 2 diabetes far better than placebo. (A1C or HbA1c measures the average glucose, or sugar, in the blood over the past two to three months.) 

Some patients taking Rybelsus also lost weight. In a second trial, funded by Novo Nordisk,  researchers tested Rybelsus for weight loss in people with obesity or excess weight who do not have type 2 diabetes and found that 50 mg of oral semaglutide led to a clinically meaningful reduction in body weight compared to placebo.

How do you take Rybelsus? 

If your health care provider prescribes Rybelsus, the manufacturer recommends taking it at the same time each day—ideally first thing in the morning—on an empty stomach with a sip (4 ounces or less) of water. Then, wait 30 minutes before eating, drinking, or taking other medications or supplements. 

It’s important to take Rybelsus on an empty stomach so it can rest on the lining of your stomach undisturbed for at least 30 minutes to be properly absorbed into the body. 

Health care providers often advise patients taking Rybelsus to make this part of their morning routine, keeping a pill bottle and a glass of water by the bedside and taking Rybelsus when their alarm sounds. ‍

How long does it take for Rybelsus to start working?

Although the medicine begins to take effect quickly, it may take several weeks to a few months to know how—or whether—the drug works for you. 

According to the complete prescribing information on its FDA-approved drug label, Rybelsus reaches maximum concentration in the body within one hour of the first dose and reaches a steady state supply after four to five weeks of daily use. 

Patients prescribed Rybelsus typically start with a 3 mg daily dose for the first thirty days to give their bodies time to get used to the medicine. If they tolerate the drug well, they’re usually stepped up to a 7 mg daily dose. After thirty days at 7 mg, their dosage may be increased to the maximum 14 mg daily dose if needed. 

Found-affiliated clinicians work with patients to determine the best option for each member, but the ultimate decision as to whether a patient is qualified for a medication rests with the provider.

How much weight can I lose on Rybelsus? 

Individual results vary, of course. However, in a pre-market clinical trial, people with type 2 diabetes who took 3 mg, 7 mg or 14 mg Rybelsus daily along with diet and exercise lost an average of between 3.7 and 9 pounds after six months, with the higher doses associated with an increased percentage of weight loss. On average, those participants weighed 192 to 196 pounds before taking Rybelsus. 

Additional post-market studies are investigating Rybelsus specifically for weight loss in adults with obesity or excess weight who do not have type 2 diabetes. One such study, called OASIS 1 and reported in The Lancet in 2023, found people who took a much larger dose (50 mg) of Rybelsus daily for 68 weeks lost, on average, 15.1% of their body weight. 

What are possible side effects of Rybelsus (semaglutide)? 

Common side effects of Rybelsus include:

• Nausea
• Abdominal pain
• Diarrhea
• Decreased appetite
• Vomiting
• Constipation

These are typically mild and are most common when starting or increasing the dosage of Rybelsus. But be sure to tell your health care professional if you experience severe stomach problems that won’t go away, including abdominal bloating or pain, acid reflux, a feeling of fullness after eating just a few bites of food, nausea, and vomiting (including vomiting undigested food eaten a few hours earlier). These may be symptoms of gastroparesis (stomach paralysis). 

Less common and more serious side effects may include: 

• Inflammation of the pancreas (pancreatitis)
• Changes in vision
• Low blood sugar (hypoglycemia). Your risk for low blood sugar may be higher if you take Rybelsus with another medicine that lowers blood sugar, such as sulfonylureas or insulin. Signs of low blood sugar may include dizziness or lightheadedness, blurred vision, anxiety, irritability or mood changes, sweating, slurred speech, hunger, confusion or drowsiness, shakiness, weakness, headache, fast heartbeat, and feeling jittery.
• Kidney problems or kidney failure. In people with kidney problems, diarrhea, nausea, and vomiting may cause a loss of fluids (dehydration) that can cause kidney problems to worsen. 
• Serious allergic reactions, including swelling of the face, lips, tongue, or throat; problems breathing or swallowing; severe rash or itching; fainting or feeling dizzy; or very rapid heartbeat.
• Gallbladder problems. Symptoms may include: pain in your upper stomach (abdomen), yellowing of skin or eyes (jaundice), fever, and clay-colored stools.
• Possible thyroid tumors, including cancer. Tell your health care provider if you notice a lump or swelling in your neck, hoarseness, trouble swallowing, or shortness of breath. These may be symptoms of thyroid cancer. 

Who should not use Rybelsus (semaglutide)? 

People with a personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 should not take Rybelsus. Do not take Rybelsus if you have ever had thyroid cancer. Rybelsus also can cause fetal harm, so if you are pregnant, breastfeeding, or planning to become pregnant, do not take Rybelsus. Find detailed side effect and risk information on our dedicated Rybelsus page.

About Found

Found is among the largest medically-supported telehealth weight care platforms in the country, having served more than 250,000 members to date. To discover your MetabolicPrint™ and start your journey with Found, take our quiz.

Found is not affiliated with Eli Lilly and Co., the owner of the registered trademarks Mounjaro® and Zepbound®, nor is it affiliated with Novo Nordisk A/S, the owner of the registered trademarks Wegovy®, Ozempic®, and Rybelsus®. The content provided is for informational purposes only and should not be used as a basis for diagnosing or treating any health condition, or for determining actual costs incurred. Always follow your health care provider’s instructions to ensure safe and effective management of your health conditions. Certain medications are only FDA-approved to treat conditions other than weight but may be prescribed to help aid in weight loss. Prescriptions are up to a medical provider’s discretion. For key risk information by drug, visit the Found medication page.