Can you do a semaglutide injection wrong?: Risks, Mistakes, and Proper Technique

October 9, 2025 •

4 min read

Yes, it is possible to do a semaglutide injection wrong, and the FDA has received reports of adverse events, including hospitalization, related to dosing errors with compounded semaglutide injectable products. Mastering the correct technique is crucial for ensuring the medication works as intended and for minimizing risks.

Quick Summary

It is possible to inject semaglutide incorrectly, affecting absorption, efficacy, and potentially causing adverse effects. Learn how to perform the injection properly, including site rotation, to avoid common mistakes and ensure medication safety.

Key Points

Possible for Error: You can perform a semaglutide injection incorrectly, and doing so can affect its effectiveness and safety.
Tissue Layer Matters: Semaglutide must be injected into the fatty subcutaneous layer; injecting into muscle or a vein can alter absorption and cause severe side effects.
Rotate Injection Sites: Rotating between the abdomen, thigh, and upper arm is crucial to prevent skin irritation, bruising, and lumps that can affect absorption.
Avoid Dosing Mistakes: Extreme caution is required with compounded semaglutide to prevent serious dosing errors, as some patients have been hospitalized due to overdoses.
Hold for the Full Dose: To ensure you get the complete dosage, hold the pen needle in place for the full recommended time (e.g., 5-10 seconds) after injection.
Never Reuse Needles: Using a fresh, sterile needle for each injection is non-negotiable to prevent infection and discomfort.

Understanding Subcutaneous Injections

Semaglutide is administered via subcutaneous injection, meaning it's delivered into the fatty tissue beneath the skin. This differs from intramuscular injections, which target muscle tissue. The subcutaneous route ensures the medication is absorbed slowly and steadily, which is vital for its effectiveness. Injecting into the wrong tissue can disrupt this process, leading to inconsistent results and side effects.

Common Semaglutide Injection Mistakes and Their Consequences

Awareness of potential errors during self-injection is key to ensuring both safety and the medication's effectiveness.

Injecting into the Wrong Site or Tissue

Injecting semaglutide into the incorrect location or tissue depth can have varied consequences:

Intramuscular (Muscle): Injecting into muscle can lead to faster-than-intended absorption, potentially intensifying gastrointestinal side effects like nausea or vomiting. This is more likely in areas with less subcutaneous fat. While generally not dangerous, it can make treatment inconsistent.
Intravenous (Vein): Injecting into a blood vessel is a serious risk that can cause a rapid drop in blood sugar (hypoglycemia) and severe side effects. Immediate medical help is needed if this occurs. Though rare with the small needles used, it's a critical error. Watch for signs of hypoglycemia such as sweating or a rapid heart rate.
Too Shallow (Intradermal): Injecting too close to the skin's surface can result in poor absorption and may cause localized pain or redness.
Too Close to the Belly Button: This area has more nerves and less fat. Injecting here can be more painful and less effective. It is recommended to inject at least 2 inches away from the navel.

Incorrect Injection Technique

Proper technique is vital for successful injection:

Not Rotating Sites: Injecting repeatedly into the same spot can cause skin issues like bruising or lumps (lipohypertrophy), which can interfere with how the medication is absorbed.
Not Holding the Pen Long Enough: Removing the needle too soon after pressing the dose button can lead to medication leakage and an incomplete dose. Follow the specific hold time recommended for your pen.
Dosing Errors: There are risks of significant dosing errors, particularly with compounded semaglutide, often due to confusion over units of measurement. Always verify the dose carefully, especially with vials and syringes.

Handling and Preparation Errors

Mistakes in handling and preparation can also compromise your injection:

Reusing Needles: Needles are single-use items. Reusing them increases the risk of infection, pain, and tissue damage.
Not Letting Alcohol Dry: Injecting through wet alcohol can cause a stinging sensation. Always let the cleaned site air dry completely.
Injecting Cold Medication: Injecting medication straight from the refrigerator can cause discomfort. Allow it to warm up to room temperature for 15-20 minutes before use.

How to Perform a Correct Semaglutide Injection

Following the correct procedure minimizes errors and ensures safety and effectiveness. Always consult your medication's instructions and your healthcare provider.

Preparation: Wash your hands and gather your supplies: pen/vial, new needle, and alcohol swab. Check the medication for clarity.
Site Selection and Cleaning: Choose an approved subcutaneous site: abdomen (at least 2 inches from navel), thigh, or upper arm. Clean the site with an alcohol swab and let it air dry.
Dose Preparation: Attach a new needle. Dial or draw up the correct dose.
Injection: Gently pinch a skin fold. Insert the needle straight in at a 90-degree angle.
Dose Delivery: Press and hold the dose button for the time specified by the manufacturer (e.g., 5-10 seconds). Wait until the dose indicator confirms completion.
Withdrawal and Disposal: Release the button and withdraw the needle. Do not rub the site. Dispose of the needle in a sharps container.

Proper vs. Improper Semaglutide Injection: A Comparison


Feature	Correct Injection	Incorrect Injection	Consequences of Error
Injection Site	Abdomen (away from navel), thigh, or upper arm.	Close to navel, scar tissue, or muscle.	Increased pain, inconsistent absorption, reduced efficacy.
Technique	Pinching skin, 90° angle, steady pressure.	Injecting without pinching or at a shallow angle.	Inconsistent absorption, medication leakage, bruising.
Needle Use	Use a new, sterile needle every time.	Reusing needles.	Increased risk of infection, skin damage, dull needle pain.
Site Rotation	Rotate weekly between approved sites.	Repeatedly using the same spot.	Lipohypertrophy, poor absorption, irritation.
Observation Time	Hold needle for 5-10 seconds after injection.	Removing the needle too quickly.	Medication leakage, incomplete dose.

Conclusion

While administering a semaglutide injection is generally straightforward, errors are possible and can impact effectiveness and safety. Mistakes such as injecting into the wrong tissue, not rotating sites, or incorrect dosing can lead to reduced benefits, increased side effects, and potential health issues. Adhering to the proper technique, using new needles, and being meticulous with site rotation and dosing, ideally under the guidance of a healthcare provider, can significantly reduce these risks and ensure the medication works as intended. For further information, particularly regarding compounded products, consulting a medical professional is crucial to avoid potentially dangerous errors.

For more detailed information on proper injection techniques, consult the official FDA guidelines regarding compounded semaglutide: FDA alerts health care providers, compounders and patients of dosing errors associated with compounded semaglutide injectable products.

Frequently Asked Questions

If you accidentally inject into the muscle instead of the fat, the medication will be absorbed more quickly, which can lead to a more intense onset of side effects like nausea or abdominal pain. It is not typically dangerous, but you should return to the proper subcutaneous technique for future doses.

Signs of improper injection include increased pain or stinging at the site, redness, or bruising. Systemic signs from altered absorption could include a sudden worsening of gastrointestinal symptoms (if injected too fast) or inconsistent therapeutic effects (if absorbed poorly).

Injecting less than two inches from the belly button can be more painful due to a higher concentration of nerves. It may also lead to less consistent absorption. The medication should be injected at least 2 inches away from the navel.

Yes, repeatedly injecting into the exact same spot can cause lipohypertrophy, where fatty lumps form under the skin. These lumps can interfere with medication absorption and reduce its effectiveness over time. Regular rotation prevents this issue.

Holding the pen for 5 to 10 seconds after pushing the dose button is essential to ensure the full dose is delivered and to prevent medication from leaking out when the needle is withdrawn.

Seeing a small amount of blood is not uncommon and is not a cause for panic. Simply apply gentle pressure to the area with a cotton ball or gauze. Do not rub the site, as this can affect medication absorption.

Compounded semaglutide can carry a higher risk of dosing errors due to variations in concentrations and measuring devices. The FDA has warned about potentially large overdoses leading to severe adverse events, including hospitalization.