Last updated: March 15, 2026
IMPORTANT: Compounded GLP-1 medications are NOT FDA-approved.
Compounded semaglutide and compounded tirzepatide are prepared by state-licensed compounding pharmacies and have not been evaluated by the FDA for safety, efficacy, or quality. The decision to use a compounded medication is made between you and your prescribing physician based on your individual medical history.
This page provides general safety information about GLP-1 receptor agonist medications, including compounded semaglutide and compounded tirzepatide. This is not a substitute for medical advice from your physician. Always discuss side effects, risks, and benefits with your prescribing healthcare provider before starting or changing any medication.
In animal studies, GLP-1 receptor agonists caused thyroid C-cell tumors, including medullary thyroid carcinoma (MTC). It is not known whether GLP-1 receptor agonists cause thyroid C-cell tumors, including MTC, in humans.
Tell your healthcare provider if you or any family member has ever had MTC or MEN 2, or if you notice a lump or swelling in your neck, hoarseness, difficulty swallowing, or shortness of breath.
The following side effects are commonly reported with GLP-1 receptor agonist medications. Most are mild to moderate and may decrease over time as your body adjusts:
If any common side effects persist or become severe, contact your healthcare provider.
The following serious side effects have been reported with GLP-1 receptor agonists. Seek medical attention immediately if you experience any of these:
Stop taking the medication and call your healthcare provider immediately if you have severe pain in your stomach area (abdomen) that will not go away, with or without vomiting. The pain may be felt going from your abdomen through to your back.
GLP-1 receptor agonists may cause gallbladder problems, including gallstones. Call your healthcare provider if you experience upper stomach pain, fever, yellowing of the skin or eyes (jaundice), or clay-colored stools.
GLP-1 receptor agonists may cause kidney problems, including kidney failure. This may happen in people who experience severe nausea, vomiting, or diarrhea leading to dehydration. Call your healthcare provider if you have decreased urination, swelling in your legs or feet, or feel confused.
The risk of low blood sugar may be increased if you use GLP-1 receptor agonists with other medications that can cause low blood sugar, such as sulfonylureas or insulin. Signs include dizziness, blurred vision, anxiety, irritability, sweating, slurred speech, hunger, confusion, shakiness, weakness, headache, fast heartbeat, or feeling jittery.
Stop using the medication and get medical help right away if you have symptoms of a serious allergic reaction, including:
Tell your healthcare provider if you have changes in vision during treatment with a GLP-1 receptor agonist, particularly if you have diabetic retinopathy.
GLP-1 receptor agonists may cause an increase in resting heart rate. Tell your healthcare provider if you feel your heart racing or pounding while at rest.
There have been postmarketing reports of suicidal ideation and behavior in patients taking GLP-1 receptor agonists. If you have suicidal thoughts or actions, stop taking the medication and call your healthcare provider or 988 (Suicide & Crisis Lifeline) immediately.
GLP-1 receptor agonists should NOT be used if you have:
Call 911 or go to the nearest emergency room if you experience:
Tell your healthcare provider about all the medications you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. GLP-1 receptor agonists may affect how other medicines work, and other medicines may affect how GLP-1 receptor agonists work. Important interactions include:
Pregnancy: GLP-1 receptor agonists should not be used during pregnancy. Animal studies have shown adverse effects on the developing fetus. If you are pregnant, planning to become pregnant, or suspect you may be pregnant, stop using the medication and tell your healthcare provider immediately. Discontinue GLP-1 receptor agonists at least 2 months before a planned pregnancy.
Breastfeeding: It is not known whether GLP-1 receptor agonists pass into breast milk. Talk to your healthcare provider about the best way to feed your baby if you are using a GLP-1 receptor agonist.
Compounded GLP-1 medications referenced on this website are prepared by state-licensed compounding pharmacies in accordance with applicable state and federal regulations. These pharmacies operate under the oversight of their respective state boards of pharmacy.
Compounded medications are not FDA-approved. The FDA does not verify the safety, efficacy, or quality of compounded preparations. Compounding is permitted under sections 503A and 503B of the Federal Food, Drug, and Cosmetic Act when certain conditions are met.
The decision to prescribe a compounded medication is made by your licensed healthcare provider based on your individual medical needs. FastHealthFacts.com does not compound, prescribe, or dispense medications.
If you have questions about GLP-1 medication safety, side effects, or your treatment plan, contact your prescribing healthcare provider directly.
For questions about the information on this website, contact us at health@fastfactsgroup.com.
To report a side effect or adverse event, contact your healthcare provider or the FDA MedWatch program at www.fda.gov/medwatch or call 1-800-FDA-1088.
This page is for informational purposes only and does not constitute medical advice. Always consult a licensed healthcare professional for medical guidance. The information on this page may not reflect the most current medical research or FDA guidance. Last reviewed: March 2026.