GLP-1 Evidence

Drug profile

Compounded GLP-1 preparations: what the trials actually show

Unapproved compounded preparation. Injection.

Updated 3 min read 14 citations

What the evidence supports

No trial evidence exists for these preparations, because they are not the products that were trialled. Regulators in several jurisdictions have warned about dosing errors and about salt forms — semaglutide sodium and semaglutide acetate — that were never studied in humans. [1]

This entry exists because the market is large and the risk is real: overdose from unfamiliar concentrations is the specific documented harm. It is not a cheaper version of the licensed drug; it is a different product.

Evidence strength across the incretin drugs profiled Of the 6 incretin drugs and preparations profiled, this shows how many sit at each level of evidence, with Compounded GLP-1 preparations graded popular but weak. Established4 drugsPromising1 drugsPopular but weak1 drugs
Compounded GLP-1 preparations is graded popular but weak. The grade describes the quality of the trial evidence, not how well the drug will suit any individual — and the one entry graded "popular but weak" is there precisely because it is widely sold and never trialled. Grades assigned from trial programme and regulatory status.

What happens when you stop

This is the part of the picture most often left out. Withdrawal trials consistently show substantial weight regain within a year of stopping, and cardiometabolic markers drifting back with it [2]. That is not a failure of the drug — it is what treating a chronic condition with a drug looks like when the drug is removed.

The practical implication is that the decision to start is a decision about a long horizon, including cost and access over that horizon, rather than about a target weight.

Muscle mass

Rapid weight loss from any cause includes lean tissue, and the incretin trials are no exception. The proportion lost as lean mass appears broadly similar to other rapid-loss methods, but the absolute loss is larger because the total loss is larger. Adequate protein and resistance training are the interventions with evidence behind them, and both are within your control while taking the drug.

Other drugs in this class

How much weight do people lose on compounded glp-1 preparations?
No trial evidence exists for these preparations, because they are not the products that were trialled. Regulators in several jurisdictions have warned about dosing errors and about salt forms — semaglutide sodium and semaglutide acetate — that were never studied in humans. Those are trial means; individual response varies widely and trial participants receive support that is part of the result.
What happens if I stop?
Most of the weight returns, typically within a year. Withdrawal trials are consistent on this and it is the single most important thing to understand before starting.
Does it cause muscle loss?
Rapid weight loss from any cause includes lean tissue. Protein intake and resistance training are the mitigations with evidence behind them.
Is a compounded version the same thing?
No. Compounded preparations are not the products that were trialled, dosing errors are documented, and some use salt forms never studied in humans.

References

Every citation below links to the original peer-reviewed record on PubMed or via DOI. Nothing here is a substitute for medical advice.

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  2. Subcutaneously administered tirzepatide vs semaglutide for adults with type 2 diabetes: a systematic review and network meta-analysis of randomised controlled trials Karagiannis T, Malandris K, Avgerinos I, et al. · Diabetologia · 2024 · Meta-analysis DOIPubMed 38613667Full text
  3. Long-Term Efficacy and Safety of Once-Weekly Semaglutide for Weight Loss in Patients Without Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials Moiz A, Levett JY, Filion KB, et al. · The American journal of cardiology · 2024 · Meta-analysis DOIPubMed 38679221
  4. EASL-EASD-EASO Clinical Practice Guidelines on the management of metabolic dysfunction-associated steatotic liver disease (MASLD) Journal of hepatology · 2024 · Clinical guideline DOIPubMed 38851997
  5. Comparative effectiveness of GLP-1 receptor agonists on glycaemic control, body weight, and lipid profile for type 2 diabetes: systematic review and network meta-analysis Yao H, Zhang A, Li D, et al. · BMJ (Clinical research ed.) · 2024 · Meta-analysis DOIPubMed 38286487Full text
  6. Quantified Metrics of Gastric Emptying Delay by Glucagon-Like Peptide-1 Agonists: A Systematic Review and Meta-Analysis With Insights for Periprocedural Management Hiramoto B, McCarty TR, Lodhia NA, et al. · The American journal of gastroenterology · 2024 · Meta-analysis DOIPubMed 38634551Full text
  7. Weight loss efficiency and safety of tirzepatide: A Systematic review Lin F, Yu B, Ling B, et al. · PloS one · 2023 · Meta-analysis DOIPubMed 37141329Full text
  8. Efficacy and Safety of Semaglutide for Weight Loss in Obesity Without Diabetes: A Systematic Review and Meta-Analysis Tan HC, Dampil OA, Marquez MM · Journal of the ASEAN Federation of Endocrine Societies · 2022 · Meta-analysis DOIPubMed 36578889Full text
  9. Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of cardiovascular outcome trials Kristensen SL, Rørth R, Jhund PS, et al. · The lancet. Diabetes & endocrinology · 2019 · Meta-analysis DOIPubMed 31422062
  10. Tirzepatide for Heart Failure with Preserved Ejection Fraction and Obesity Packer M, Zile MR, Kramer CM, et al. · The New England journal of medicine · 2025 · Randomised controlled trial DOIPubMed 39555826
  11. Tirzepatide for Obesity Treatment and Diabetes Prevention Jastreboff AM, le Roux CW, Stefanski A, et al. · The New England journal of medicine · 2025 · Randomised controlled trial DOIPubMed 39536238
  12. Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist, in Early Type 2 Diabetes Rosenstock J, Hsia S, Nevarez Ruiz L, et al. · The New England journal of medicine · 2025 · Randomised controlled trial DOIPubMed 40544435
  13. Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment Wharton S, Aronne LJ, Stefanski A, et al. · The New England journal of medicine · 2025 · Randomised controlled trial DOIPubMed 40960239
  14. Once-Weekly Semaglutide in Persons with Obesity and Knee Osteoarthritis Bliddal H, Bays H, Czernichow S, et al. · The New England journal of medicine · 2024 · Randomised controlled trial DOIPubMed 39476339