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Important Safety Information

Compounded semaglutide

Read this before starting treatment. It is a summary of the most important safety information, not a complete list.

Last updated 8 August 2026

Boxed warning — risk of thyroid C-cell tumours

In studies in rodents, semaglutide and medications that work the same way caused thyroid C-cell tumours, including medullary thyroid carcinoma (MTC). It is not known whether compounded semaglutide causes these tumours in people.

Do not use compounded semaglutide if you or any of your family have ever had medullary thyroid carcinoma, or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).

Tell your provider immediately if you develop a lump or swelling in your neck, hoarseness, trouble swallowing, or shortness of breath.

About compounded medication. The medication described here is prepared for an individual patient by a state-licensed compounding pharmacy. It is not FDA-approved for safety and effectiveness, and the FDA does not review compounded preparations for quality, strength or purity before they are dispensed. The safety information below is drawn from the FDA-approved labelling for the same active ingredient.

What this medication is for

Compounded semaglutide is prescribed as part of a provider-guided weight-management program, alongside a reduced-calorie diet and increased physical activity. It is prescribed only after a licensed provider reviews your health history and determines it is clinically appropriate for you. It is not appropriate for everyone, and it is not a substitute for lifestyle change.

Do not use this medication if

  • You or a family member has had medullary thyroid carcinoma (MTC).
  • You have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).
  • You have had a serious allergic reaction to semaglutide and medications that work the same way or to any ingredient in the preparation.
  • You are pregnant, trying to become pregnant, or breastfeeding.

Tell your provider before starting if you

  • Have had pancreatitis, gallbladder disease, or gallstones.
  • Have kidney disease, or have had severe problems with your stomach such as gastroparesis.
  • Have type 2 diabetes — especially if you take insulin or a sulfonylurea, which raise the risk of low blood sugar when combined with this medication.
  • Have diabetic retinopathy.
  • Have a history of depression, mood changes, or suicidal thoughts.
  • Take any other medication, including anything for weight loss, and any supplement.
  • Have a planned surgery or procedure requiring anaesthesia or deep sedation — these medications slow stomach emptying, and your anaesthesia team must be told.

Common side effects

Nausea, vomiting, diarrhoea, constipation, abdominal pain, indigestion, burping, bloating, fatigue, headache, dizziness, and injection-site reactions. These are most common when starting and when the dose is increased, and often settle over time.

Serious side effects — stop and seek care

  • Pancreatitis. Severe, persistent abdominal pain, with or without vomiting, that may radiate to your back. Stop the medication and seek care.
  • Gallbladder problems. Upper-right abdominal pain, fever, jaundice, or clay-coloured stools.
  • Kidney injury. Usually from dehydration caused by vomiting or diarrhoea. Keep up fluids and tell your provider if you cannot.
  • Low blood sugar. Shakiness, sweating, confusion, fast heartbeat — particularly if you also take insulin or a sulfonylurea.
  • Serious allergic reaction. Swelling of the face, lips, tongue or throat, difficulty breathing, or severe rash. Call 911.
  • Changes in vision, or worsening diabetic retinopathy.
  • Mood changes, depression, or thoughts of self-harm. Tell your provider straight away.
  • Thyroid tumours. A lump or swelling in the neck, hoarseness, trouble swallowing, or shortness of breath.

Storage and handling

Keep your medication refrigerated as instructed on the label, protected from light, and out of reach of children. Do not use it after its beyond-use date. Never share your medication, and never share needles or syringes. Dispose of used needles in an approved sharps container.

Using it correctly

Doses are prescribed in milligrams, but syringes are marked in units, and the conversion depends on the concentration of your vial. Getting this wrong is the single most common and most dangerous error we see. Use our dose calculator, and if the number does not match what you expect, stop and message your provider before injecting.

Florida weight-loss consumer disclosures

Required by Fla. Stat. § 501.0575 for every weight-loss patient:

  • RAPID WEIGHT LOSS MAY CAUSE SERIOUS HEALTH PROBLEMS.
  • CONSULT YOUR PERSONAL PHYSICIAN BEFORE STARTING ANY WEIGHT-LOSS PROGRAM.
  • ONLY PERMANENT LIFESTYLE CHANGES PROMOTE LONG-TERM WEIGHT LOSS.
  • QUALIFICATIONS OF THIS PROVIDER ARE AVAILABLE UPON REQUEST.

You also have the right, on request, to receive: a statement of the health risks and the components of the program; an itemised price list; the actual or estimated duration of the program; and the name, address and qualifications of the dietitian or nutritionist who reviewed the program.

This summary is not complete

The information above is a summary and does not list every possible risk, interaction or side effect. It does not replace the instructions your provider gives you or the information supplied with your medication. Discuss your full health history and all medications you take with your provider before starting treatment.

Reporting a problem

Tell your provider about any side effect. You can also report side effects directly to the FDA at fda.gov/medwatch or by calling 1-800-FDA-1088. If you think you are having a medical emergency, call 911.