Most people taking GLP-1 drugs—such as Ozempic, Mounjaro, Wegovy, and Zepbound—can safely fast for religious observances like Yom Kippur, but they should plan ahead and take certain precautions. These medications are used to treat diabetes or aid in weight loss and are prescribed to millions worldwide, including up to one in eight adults in the United States. Religious fasting, such as Yom Kippur, which lasts about 25 hours, can affect the body’s metabolism and may interact with these medications. People fasting for religious or cultural reasons should consult their doctor and take steps to ensure their health is not compromised. GLP-1 drugs work by mimicking a natural gut hormone called glucagon-like peptide 1 (GLP-1), which helps lower blood sugar by stimulating insulin release. These drugs also slow stomach emptying, which reduces appetite and supports weight loss. However, they can cause side effects like nausea, dizziness, and constipation. Fasting may worsen these effects, especially for people with sensitive stomachs or those who are increasing their medication dosage. For people on weekly GLP-1 injections, the most common form of dosing, it's important to follow the regular schedule even during a fast. These medications stay in the body for the full week, so skipping or moving a dose before fasting could affect blood sugar control or weight management. If the injection falls on Yom Kippur, it can usually be taken as scheduled, but some people may experience nausea and choose to delay it after the fast, if approved by their doctor. Those on daily injections may need to adjust the timing, especially if they are managing diabetes, to avoid stomach discomfort. Fasting while on GLP-1 medications carries greater risks for people with diabetes, particularly those using insulin or other drugs that lower blood sugar. These medications can interact with GLP-1 drugs to increase the risk of dangerously low blood sugar levels. People with Type 1 diabetes, poorly controlled diabetes, or other specific health conditions are often advised not to fast. If fasting is planned, it's crucial to consult a doctor, monitor blood sugar levels closely, and be ready to break the fast if symptoms like dizziness, confusion, or nausea arise. Proper hydration and a balanced meal to break the fast are also essential to avoid complications.