Key takeaways
FDA-approved semaglutide products include Ozempic, Wegovy, and Rybelsus. They have undergone rigorous testing for safety and efficacy. Compounded semaglutide is not FDA approved and may come with risks like dosing errors and contamination.
- While compounded semaglutide was temporarily allowed during drug shortages, it must be phased out by April or May 2025, depending on the facility type. This deadline could be extended depending on ongoing court cases.
- Compounded semaglutide dosing typically follows a similar schedule to FDA-approved versions, starting with the lowest dose and gradually increasing the dose under the guidance of a healthcare provider.
Clinical studies show that semaglutide alone is effective for weight loss and blood sugar management. There is no data on the use of semaglutide in combination with vitamin B12.
Consult your healthcare provider for personalized medical advice about the use of semaglutide and/or B12.
With the skyrocketing popularity of injectable medications Ozempic and Wegovy, a shortage inevitably followed. Ozempic and Wegovy (and Rybelsus, which is oral semaglutide) are GLP-1 receptor agonists (glucagon-like peptide-1 receptor agonists, commonly referred to as GLP-1s) and are the only FDA-approved drugs that contain the active ingredient semaglutide.
These drugs are taken once weekly by subcutaneous injection (injection under the skin) and are used for improving blood sugar levels, chronic weight management, and cardiovascular risk reduction, depending on the specific drug. However, due to the shortage, compounding pharmacies and facilities were allowed to temporarily produce compounded semaglutide to meet the high demand—even though compounded semaglutide injections are not FDA approved. Some facilities add B12 to their compounds, in addition to semaglutide. Now that the FDA has confirmed the shortages have been resolved, companies have been informed they can no longer offer compounded semaglutide after a transition period. However, it is unclear whether some facilities will continue to find ways to offer these alternative versions. What is the benefit of adding B12? Does it make semaglutide work better? Keep reading to find out more about compounded semaglutide and B12.
When should you use compounded semaglutide?
The U.S. Food and Drug Administration (FDA) recommends using FDA-approved semaglutide products, like Wegovy, Ozempic, or Rybelsus, whenever possible. This is because the drug has gone through rigorous testing for safety and efficacy.
Compounded medications are not subject to the same high standards as FDA-approved prescription medications and over-the-counter (OTC) drugs. While many people achieve success with compounded semaglutide, the FDA also warns of potential problems with compounded semaglutide products, such as dosing errors that can lead to serious side effects and hospitalization, as well as contamination and inaccurate amounts of medicine in the compound.
While it’s best to use FDA-approved drugs, if you use compounded semaglutide, you should only do so under the guidance of your healthcare provider, using a reputable compounding pharmacy or facility. It remains to be seen how long compounded semaglutide products will be available. The FDA has given compounding pharmacies and facilities a deadline of April 22, 2025 or May 22, 2025 (depending on the type of compounding pharmacy or facility) to stop offering compounded semaglutide. However, this deadline could be extended, pending the outcome of ongoing court cases. After this time, it is uncertain whether some facilities may seek alternative ways to continue offering compounded versions.
Another consideration is that not everyone can use semaglutide, whether FDA-approved or compounded. You should not use semaglutide if you are allergic to semaglutide or any ingredient in the medicine. People with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) or with a personal or family history of medullary thyroid carcinoma (MTC) should not use semaglutide.
What is the dosing for compounded semaglutide?
Dosing for compounded semaglutide is typically the same as dosing for FDA-approved versions of semaglutide—but with varying higher doses, as Ozempic and Wegovy have slightly different higher doses.
Your healthcare provider will determine the best dosing schedule for you. You will start at the lowest dose, gradually increasing the dose as directed by your provider, to a dose that works effectively with the least amount of side effects or adverse reactions. Common side effects of semaglutide include gastrointestinal side effects such as nausea, vomiting, diarrhea or constipation, abdominal pain, gas, and indigestion. Other side effects are possible, too—you can ask your healthcare provider for a full list of side effects. More serious side effects that require urgent or emergency medical help may include allergic reactions, acute kidney injury, and inflammation of the gallbladder.
A typical dosing schedule would look something like this:
- Starting dose: 0.25 mg semaglutide once per week for four weeks.
- After four weeks, increase the weekly dose to 0.5 mg semaglutide for at least four weeks.
- Your healthcare provider will continue to gradually increase the dose, if needed, every month.
For Ozempic, the highest dose is 2 mg weekly, while Wegovy’s highest doses are 1.7 mg or 2.4 mg once weekly. If using compounded semaglutide, your healthcare provider would likely mimic a similar type of schedule.
Is semaglutide with B12 safe?
So, is semaglutide with B12 safe? Do you even need this combination as a weight-loss medication? Clinical studies found that semaglutide was effective on its own—without B12—finding that people lost an average of 15% of body weight over 68 weeks. Semaglutide has not been studied in combination with B12. For most people, semaglutide without B12 will work effectively—although lifestyle changes like diet and exercise are typically recommended as well.
Vitamin B12 is an essential nutrient. It is important to the body for functions such as supporting the central nervous system, DNA synthesis, and red blood cell formation. Some research has found that people with obesity had lower levels of vitamin B-12, but further studies are needed to confirm a link between weight and B12 levels. One very small study found that people who used semaglutide had lower B12 levels, but these patients also had bariatric surgery prior to using semaglutide—so it’s hard to say if using semaglutide would lead to a B12 deficiency, requiring you to need additional B12.
According to the Cleveland Clinic, if you have low B12 levels (as measured on lab tests), adding B12 can help with your symptoms and increase your energy, which could help with your weight loss efforts. However, B12 supplementation is not directly associated with weight loss. What’s more, if your B12 levels are adequate, adding B12 will not offer any benefits, including weight loss.
There is no data on the combination of semaglutide with B12. And, as mentioned above, compounded semaglutide products (with or without B12) are not held to the same standards as FDA-approved drugs. It’s always best to schedule an in-person consultation or virtual consultation with your healthcare provider for personalized medical advice, as your provider will be familiar with your medical history and family history. You can always ask your provider to check your B12 levels. If you have low B12 levels, is compounded semaglutide with B12 the answer? A better bet may be to use an FDA-approved version of semaglutide (such as Wegovy) as well as an FDA-approved prescription B12 injection. Compounded semaglutide with B12 may seem like a convenient option. However, it’s important to consider FDA-approved treatments and speak with your doctor to determine the best treatment for your individual needs for blood sugar control and/or your weight loss journey. Your provider can weigh factors, such as the potential health benefits versus the potential side effects and risks, to determine the best treatment for you.
- What does FDA regulate? U.S. Food and Drug Administration (2024)
- Compounding when drugs are on FDA’s drug shortages list, U.S. Food and Drug Administration (2024)
- FDA’s concerns with unapproved GLP-1 drugs used for weight loss, U.S. Food & Drug Administration (2025)
- FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products, U.S. Food and Drug Administration (2024)
- FDA clarifies policies for compounders as national GLP-1 supply begins to stabilize, U.S. Food & Drug Administration (2025)
- Ozempic, DailyMed (2025)
- Wegovy, DailyMed (2024)
- Once-weekly semaglutide in adults with overweight or obesity, New England Journal of Medicine (2021)
- Vitamin B12, National Institutes of Health Office of Dietary Supplements (2024)
- Vitamin B12 injections: What they can and can’t do, Cleveland Clinic (2024)
- Once-weekly semaglutide administered after laparoscopic sleeve gastrectomy: Effects on body weight, glycemic control, and measured nutritional metrics in Japanese patients having both obesity and type 2 diabetes, Obesity Pillars (2024)
- Inverse association between serum vitamin B12 concentration and obesity among adults in the United States, Frontiers in Endocrinology (Lausanne) (2019)