GLP-1 questions, answered in plain English

There's no single number for everyone, so ask your prescriber or a registered dietitian—especially if you have kidney disease. For context: the standard adult recommendation is 0.8 g of protein per kg of body weight per day, and a 2025 joint advisory from four obesity and nutrition organizations notes that higher targets (around 1.2–1.6 g/kg/day) have been proposed during active weight loss. A JAMA Internal Medicine patient guide suggests starting meals with protein (about 20–30 g) and using protein shakes if your appetite is very low.

Sources: Joint Advisory: Nutritional priorities to support GLP-1 therapy (ACLM, ASN, OMA, The Obesity Society), 2025; JAMA Internal Medicine Patient Page: I Am Taking a GLP-1 Weight-Loss Medication—What Should I Know? (2025)

Some of the weight lost on any big weight-loss effort is lean mass, and GLP-1 medicines are no exception. Experts recommend two main defenses: getting enough protein and doing regular resistance (strength) training. Both are emphasized in the 2025 joint nutrition advisory on GLP-1 therapy.

Sources: Joint Advisory: Nutritional priorities to support GLP-1 therapy (ACLM, ASN, OMA, The Obesity Society), 2025; CDC: Physical activity guidelines for adults

Nausea is one of the most common side effects, especially when starting or increasing a dose. Practical tips from medical sources: eat smaller meals, stop when you feel full, eat slowly, and go easy on fried and high-fat foods. Call your prescriber if nausea or vomiting is severe or won't stop—losing fluids can lead to dehydration, and the drug labels warn this can cause kidney problems.

Sources: JAMA Internal Medicine Patient Page: I Am Taking a GLP-1 Weight-Loss Medication—What Should I Know? (2025); Wegovy (semaglutide) Prescribing Information — Novo Nordisk; Zepbound (tirzepatide) Prescribing Information — Eli Lilly

Constipation is listed as a common side effect on GLP-1 labels. General steps include adding fiber gradually, drinking enough fluids, and staying active. Ask your prescriber or pharmacist before starting a regular laxative or fiber supplement, and get help if you have severe belly pain.

Sources: NIDDK (NIH): Eating, Diet & Nutrition for Constipation; Zepbound (tirzepatide) Prescribing Information — Eli Lilly

Yes, hair loss is listed on both the Zepbound and Wegovy labels. Zepbound's label notes it was associated with weight reduction and reported more often in women. Shedding during rapid weight loss is often temporary, but talk to your doctor if it worries you—they can check for other causes such as low iron or thyroid issues.

Sources: Zepbound (tirzepatide) Prescribing Information — Eli Lilly; Wegovy (semaglutide) Prescribing Information — Novo Nordisk

Fatigue is listed as a side effect on GLP-1 labels. Eating much less, not getting enough protein, and not drinking enough can all play a part. If tiredness is new, severe, or comes with dizziness, tell your prescriber.

Sources: Zepbound (tirzepatide) Prescribing Information — Eli Lilly; Wegovy (semaglutide) Prescribing Information — Novo Nordisk; Joint Advisory: Nutritional priorities to support GLP-1 therapy (ACLM, ASN, OMA, The Obesity Society), 2025

GLP-1s can dull thirst and appetite, and vomiting or diarrhea can cause you to lose fluids. The labels warn that dehydration from these side effects has been linked to acute kidney injury. Sip fluids through the day, and consider an electrolyte drink if you're losing fluids—but check with your doctor if you limit sodium or fluids for a heart or kidney condition.

Sources: Zepbound (tirzepatide) Prescribing Information — Eli Lilly; Wegovy (semaglutide) Prescribing Information — Novo Nordisk

Studies show many people regain weight after stopping. In the STEP 1 extension, people who stopped semaglutide regained about two-thirds of the weight they had lost within a year. In STEP 4, people switched to placebo regained weight (+6.9%) while those who stayed on semaglutide kept losing (−7.9%). In SURMOUNT-4, people switched from tirzepatide to placebo regained 14% versus a further 5.5% loss for those who continued. Never stop or change your dose without talking to your prescriber.

Sources: Wilding et al. Weight regain after withdrawal of semaglutide: STEP 1 extension. Diabetes Obes Metab, 2022 (PubMed); Rubino et al. STEP 4 randomized withdrawal trial. JAMA, 2021 (PubMed); Aronne et al. SURMOUNT-4: continued tirzepatide for weight maintenance. JAMA, 2024 (PubMed)

Options depend on your coverage: (1) If you have commercial insurance that covers the drug, the makers' savings cards can bring costs down to as little as $25 for eligible people. (2) If you're paying cash, Lilly and Novo Nordisk sell brand-name medicines directly—for example, Zepbound vials and KwikPens start at $299/month on LillyDirect, and Wegovy is $199/month for new patients' first two fills (through Dec. 31, 2026), then $349/month. (3) TrumpRx.gov lists these cash prices in one place. (4) Eligible people with Medicare Part D may qualify for the Medicare GLP-1 Bridge at $50/month. Prices change—confirm on the official pages.

Sources: Zepbound savings & insurance options — Eli Lilly; LillyDirect: Zepbound self-pay — Eli Lilly; Wegovy price guide — NovoCare (Novo Nordisk); White House fact sheet: TrumpRx.gov launch (Feb 2026); Medicare.gov: Weight loss drugs (Medicare GLP-1 Bridge)

Starting July 1, 2026, the temporary Medicare GLP-1 Bridge covers Wegovy (injection or tablet), Foundayo, and Zepbound KwikPen for eligible people with Medicare drug coverage, with a $50 monthly copay. Eligibility is based on age, BMI, and certain health conditions, and your provider must certify you're in a diet-and-exercise program. Check Medicare.gov for the full criteria.

Sources: Medicare.gov: Weight loss drugs (Medicare GLP-1 Bridge)

No. Compounded versions are not FDA-approved, which means the FDA does not review them for safety, effectiveness, or quality before they're sold. The FDA has warned about dosing errors and fraudulent products. That's why GLP1 Sidekick only lists FDA-approved, brand-name options and the official programs that sell them.

Sources: FDA: Concerns with Unapproved GLP-1 Drugs Used for Weight Loss

Yes. The FDA approved the Wegovy pill (oral semaglutide) for weight management in December 2025, and Lilly's Foundayo (orforglipron) on April 1, 2026. Rybelsus (oral semaglutide) is approved for type 2 diabetes. Your prescriber can tell you whether a pill or an injection fits you better.

Sources: Wegovy pill — Novo Nordisk; Eli Lilly: FDA approves Foundayo (orforglipron), April 1, 2026

Ozempic and Wegovy both contain semaglutide; Mounjaro and Zepbound both contain tirzepatide. The difference is what each is FDA-approved for and at what doses: Ozempic and Mounjaro are approved for type 2 diabetes, while Wegovy and Zepbound are approved for chronic weight management (with some additional approved uses listed on their labels).

Sources: NIDDK (NIH): Prescription Medications to Treat Overweight & Obesity; Ozempic (semaglutide) Prescribing Information — Novo Nordisk; Mounjaro (tirzepatide) Prescribing Information — Eli Lilly; Wegovy (semaglutide) Prescribing Information — Novo Nordisk; Zepbound (tirzepatide) Prescribing Information — Eli Lilly

Tell your surgeon and anesthesiologist that you take a GLP-1, because these medicines slow stomach emptying. 2024 guidance from the American Society of Anesthesiologists and other societies says most people can keep taking them before elective surgery, while those at higher risk (for example, early in dose increases or with GI symptoms) may need a 24-hour liquid diet or other steps. Follow your care team's instructions.

Sources: American Society of Anesthesiologists: multi-society GLP-1 guidance before surgery (2024)

Zepbound's label says it may make birth control pills less effective, and advises switching to a non-oral method or adding a barrier method for 4 weeks after starting and after each dose increase. Wegovy's label advises stopping at least 2 months before a planned pregnancy. These medicines aren't recommended during pregnancy—talk to your prescriber if you're planning or could become pregnant.

Sources: Zepbound (tirzepatide) Prescribing Information — Eli Lilly; Wegovy (semaglutide) Prescribing Information — Novo Nordisk

Yes—GLP-1 medicines are approved for use alongside a reduced-calorie diet and more physical activity. The CDC recommends adults get at least 150 minutes of moderate activity a week plus muscle-strengthening activities at least 2 days a week, and strength training is especially helpful for protecting muscle during weight loss.

Sources: CDC: Physical activity guidelines for adults; NIDDK (NIH): Prescription Medications to Treat Overweight & Obesity; Joint Advisory: Nutritional priorities to support GLP-1 therapy (ACLM, ASN, OMA, The Obesity Society), 2025

When you eat much less, it's harder to get enough vitamins and minerals. The 2025 joint advisory lists preventing nutrient deficiencies as a priority for people on GLP-1 therapy. Ask your clinician whether you need a multivitamin or lab tests—don't start high-dose supplements on your own.

Sources: Joint Advisory: Nutritional priorities to support GLP-1 therapy (ACLM, ASN, OMA, The Obesity Society), 2025

The labels list serious risks including pancreatitis (severe belly pain that may spread to your back), gallbladder problems, kidney problems from dehydration, serious allergic reactions, and low blood sugar when combined with certain diabetes medicines. They also carry a boxed warning about thyroid C-cell tumors seen in animal studies. Seek medical care right away for severe symptoms, and read the Medication Guide that comes with your prescription.

Sources: Zepbound (tirzepatide) Prescribing Information — Eli Lilly; Wegovy (semaglutide) Prescribing Information — Novo Nordisk; Cleveland Clinic: GLP-1 Agonists

Tell your prescriber first. You can also report side effects to the FDA through MedWatch (online or 1-800-FDA-1088), or to the drug's manufacturer.

Sources: FDA MedWatch: Safety information and adverse event reporting