Semaglutide is one of the ‘wonder drugs’ that revolutionized the treatment of adults suffering from Type 2 diabetes, and then went on to become a popular option for patients looking to lose weight.
Semaglutide is what is known as a glucagon-like peptide 1 (GLP-1) receptor agonist. “Agonist” means that the substance acts as a booster at the point where a molecule interacts with a cell. (The opposite action is labeled “antagonist”, which describes the action of blocking the point where the molecule would normally interact).
GLP-1 is a hormone produced in the gut that is released in response to ingestion of food. Semaglutide works by slowing down digestion and this stimulates the production of more natural insulin. This compares with other therapies for diabetes, which mostly involve direct intake of external insulin either by injection or oral medication.
Ozempic is the earliest form of semaglutide therapy, and requires a weekly self-administered injection. Rybelsus is an oral tablet version of the same drug, taken daily.
More recently, semaglutide is also being prescribed to help weight loss. Its main effect in these cases is how it works as an appetite suppressant, because of the primary action of slowing down digestion, leaving people feeling full for longer after eating smaller meals.
What are the side effects of Ozempic and Rybelsus?
Like all other drugs, there can be mild or sometimes more serious side effects. These can vary from person to person and there are no hard-and-fast rules. Your doctor would have weighed out the balance of risks and benefits when deciding to prescribe semaglutide therapy, and in making a choice between Ozempic and Rybelsus. One of the factors considered would be the slightly differing side-effects in Ozempic compared to Rybelsus.
Shared mild side effects of semaglutide:
All of the following side effects were reported in clinical trials, and are expected to fade or become less as you get used to the drug. This is the main reason why both Ozempic and Rybelsus are administered in a program of steadily increasing strengths, allowing your body to adjust and adapt. In any case, if the symptoms persist, or get worse, you should report this to the prescribing physician.
| Nausea | Nausea is the most frequently reported side effect, occurring for nearly one fifth of cases and sometimes accompanied by vomiting. It is most commonly caused by overeating, or eating too quickly. You can avoid it by eating smaller meals more frequently each day (5-6 small meals instead of two or three large ones) and avoiding triggers like high-fat and very spicy foods. |
| Diarrhea | Diarrhea has been reported by about one in ten patients. It is more common in people getting the full dose of semaglutide. |
| Stomach ache | Mild aches can be felt after eating. If they become acute or persist, it may be a sign of a more serious side effect on the gallbladder (see below) and you should consult with your doctor immediately. |
| Hypoglycemia (low blood sugar) | The purpose of Ozempic and Rybelsus is to lower blood sugar levels, but unlike for insulin treatments that can accidentally overdose and induce hypoglycemic shock, it is a self-controlling process and cannot on its own produce too much insulin. However, if your doctor has prescribed semaglutide together with another insulin or sulfonylurea therapy, then there is the risk of over-production of insulin and hypoglycemia. |
| Mild allergic reaction | Some slight itching or signs of a rash may be transient. However, see also in the table below concerning serious side-effects in case the allergic reaction is more severe. |
Specific mild side-effects of Ozempic:
Unlike with Rybelsus, patients in clinical trials exhibited some slight feelings of fatigue. As well, because Ozempic is administered by subcutaneous injection, there can be some reactions like pruritus, swelling or inflammation at the injection site.
Serious side effects of semaglutide.
Although very rare, there have been reports of the following side-effects. In any such event, report immediately back to the prescribing physician.
| Pancreatitis | Signs of inflammation of the pancreas (pancreatitis) include severe and persistent pain in the abdomen with or without vomiting. The pain can radiate from the abdomen around to the back. |
| Changes in vision | Any blurring or double-vision |
| Allergic reactions | Symptoms of a serious allergic reaction include swelling of the face, lips, tongue or throat; problems breathing or swallowing; a severe rash or itching; fainting or feeling dizzy; very rapid heartbeat. If any of these are seen shortly after taking a dose of semaglutide, call 911 or go immediately to an emergency room. |
Serious side effects specific to Ozempic:
Only with Ozempic, not Rybelsus, patients can get gallbladder problems which may include pain in the upper abdomen, with jaundice (yellowing of the skin or eyes), fever and clay-colored stools.
