Dr Nick Fuller
Leading Obesity Expert at the University of Sydney and founder of Interval Weight Loss.
Semaglutide has become one of the most talked-about medications for weight loss, with Ozempic being the branded, TGA-approved version widely prescribed in Australia. Meanwhile, compounded semaglutide has emerged as a “customised” alternative, often marketed as cheaper or more flexible in dosing. But are they really the same? While both contain the same active ingredient, there are significant differences in manufacturing, regulation, quality control, and legal oversight. Understanding these distinctions is crucial before considering which option is right for you. In this article, we’ll break down what’s inside compounded semaglutide, how Ozempic works, the key differences, and scenarios when each may be appropriate.
What’s Included in Compounded Semaglutide
Compounded semaglutide typically contains the active GLP-1 peptide identical to Ozempic, but it is prepared by a registered compounding pharmacy to meet a specific patient’s prescription. These formulations may include stabilisers or preservatives that differ from the branded version, and the dosage can be adjusted to suit individual needs. However, compounded semaglutide lacks the extensive testing, standardisation, and regulatory oversight that accompany commercially manufactured Ozempic, meaning potency, sterility, and consistency can vary between batches.
How Ozempic Works
Ozempic is a TGA-approved medication containing semaglutide in a standardised, prefilled pen designed for once-weekly administration. It works by mimicking the GLP-1 hormone to regulate appetite, slow gastric emptying, and improve blood sugar control. Extensive clinical trials have demonstrated its efficacy and safety for both type 2 diabetes and weight management, providing predictable results and well-documented side effect profiles, which compounded versions cannot fully guarantee.
Key Differences Between Compounded Semaglutide and Ozempic
Ozempic has full TGA and international regulatory approval for diabetes and weight management, ensuring rigorous safety and efficacy standards. Compounded semaglutide, however, is only approved on a patient-specific basis, meaning it does not have formal approval for general weight loss use. This difference is critical, as it impacts legal oversight, safety monitoring, and long-term reliability.
Ozempic is mass-produced in controlled pharmaceutical facilities with strict quality assurance and sterility protocols. Compounded semaglutide is prepared in individual pharmacies, which follow compounding regulations but may lack the industrial-level quality controls of commercial manufacturing. This can lead to variations in potency or consistency between batches.
Branded medications undergo routine testing to ensure every pen contains the exact dosage and purity. Compounded semaglutide may vary slightly depending on preparation methods, making it less predictable in effect and potentially affecting safety and outcomes.
Ozempic uses pharmaceutical-grade semaglutide sourced under regulated supply chains. Compounded versions may source the peptide from third-party suppliers, which can affect reliability, quality, and even sterility.
Ozempic pens deliver a precise, standardised dose each week. Compounded semaglutide dosing can be customised, which is useful medically in certain cases but also introduces risk if preparation is inaccurate or instructions are unclear.
Ozempic comes in a prefilled, user-friendly pen designed for home use, with safety features to reduce dosing errors. Compounded semaglutide may come in vials requiring self-drawing and injection, which increases the risk of dosing mistakes and contamination.
Compounded semaglutide is often marketed as cheaper due to reduced regulatory compliance costs. Ozempic, being a branded, approved medication, is generally more expensive but includes safety, insurance coverage, and predictable results.
During supply shortages, compounded semaglutide may be used as a temporary alternative under medical supervision. Ozempic’s availability is subject to manufacturer supply, which can occasionally be limited in Australia.
Both medications require prescription and oversight, but compounded semaglutide must be prescribed and monitored more closely due to variability in preparation and limited long-term data.
Ozempic carries clear legal protections as a TGA-approved drug, ensuring both patient safety and legal compliance. Compounded semaglutide is legal only when prepared and prescribed correctly, and improper use may breach Australian regulations.
Why Compounded Semaglutide Is Considered Cheaper Than Ozempic
The lower cost of compounded semaglutide usually comes from fewer regulatory hurdles, absence of mass-production expenses, and limited brand premium. However, this cost saving comes at the expense of standardisation, quality control, and long-term safety data. While cheaper upfront, compounded versions may carry hidden risks that require careful consideration and medical supervision.
When to Choose Compounded Semaglutide
Compounded semaglutide may be appropriate in certain circumstances:
Branded medication is unavailable due to shortages
Cost is a major limiting factor
A licensed doctor recommends compounding based on patient-specific needs
A registered compounding pharmacy is used to ensure sterility and accuracy
Customised dosing is medically required due to tolerance, side effects, or other health factors
When to Choose Ozempic
Ozempic remains the preferred option in many cases:
FDA or TGA-approved medication is required for legal and safety compliance
Consistent dosing and formulation are important for predictable results
Long-term safety data is a priority for sustained weight management
Insurance or subsidy coverage reduces financial barriers
Standard pen delivery system provides convenience and reduces dosing errors
Conclusion
Compounded semaglutide and Ozempic contain the same active ingredient, but they are not equivalent in terms of regulation, quality, safety, and reliability. Compounded semaglutide can be useful in select cases, such as shortages, customised dosing, or cost limitations, but it requires careful oversight by a licensed doctor and a registered compounding pharmacy. Ozempic remains the standard for predictable, safe, and TGA-approved treatment. Choosing the right option depends on availability, medical necessity, and prioritising both efficacy and safety in your weight management journey.
Dr Nick Fuller is the founder of Interval Weight Loss and is a leading obesity expert at the University of Sydney with a Ph.D. in Obesity Treatment. Dr Fuller is also the author of three best-selling books and his work been published in top ranked journals in the medical field, including JAMA, Lancet and American Journal of Clinical Nutrition.