Testosterone: How to Recognize an Injection Site Reaction

Even though the label on your vial of testosterone may indicate an intramuscular injection (in the muscle), many patients complete a subcutaneous injection typically in the belly. The absorption rate differs slightly, but the benefit is the same.

Sometimes injecting testosterone can cause a mild reaction at the injection site. For most individuals, the body typically adjusts to this with time.

An important skill is for a patient to understand what constitutes a mild vs. serious injection site reaction.

Warning Signs of Serious Injection Site Reactions

Serious injection site reactions include:

• Persistent and worsening pain over 24 hours or more

• Excessive swelling and redness

• Fever and signs of infection

• Chills and night sweats

• Feelings of fatigue or lethargy

• Shortness of breath

Below, we will explore the symptoms of an injection site reaction in greater detail, for both intramuscular and subcutaneous TRT injections.

Lucidity Health specializes in testosterone replacement therapy. One of the initial recommendations for patients is to start their therapy with a simple subcutaneous injection into the belly fat using an insulin 27-gauge syringe. Testosterone has a few different types of oil bases. Grapeseed Oil (GSO) is most commonly used by compound pharmacies. Medium-chain triglyceride (MCT) is gaining popularity for its purity and pronounced water-like viscosity. MCT oil injections can be completed with smaller (higher gauge) syringes, such as 30- or 31-gauge syringes.

For patients who cannot fathom injecting themselves with testosterone, other alternatives include topical creams and even oral testosterone. Generally, those who have some trepidation about injecting do fine once they learn a proper technique.

At Lucidity Health, we have numerous patients who use subcutaneous TRT injections on a regular basis without ill effects. Any patient who is worried about an injection site reaction or experiencing any symptoms following an injection is encouraged to reach out to our team for an immediate response.

What Are Injection Site Reactions?

Injection site reactions generally occur within hours to 48 hours post-injection. An injection site reaction is a local response at the site of injection or the surrounding tissue.

• Some injection site reactions involve an irritation of the local tissues by the injected material.

• Injection site reactions may be caused by an immune response, which typically results in mild inflammation and can be resolved with antihistamines.

Typical injection site reactions generally disappear in one to seven days and become milder with subsequent injections as the body accustoms itself to them over time. These very seldom cause adverse events, although they can occur if needles are injected into the wrong area.

Read on for more information about techniques for testosterone injections. 

Common Mild Reactions vs. Serious Ones

Let's look in greater detail at the difference between mild and serious reactions. More serious adverse reactions are rare, especially with subcutaneous or intramuscular TRT shots. However, reactions can vary widely depending on the substance.

Mild Injection Site Reactions

Mild injection reactions may cause:

• Redness

• Mild pain

• Swelling

• Itching

• A warm feeling in the injection area

• Small nodules, which are very common, especially in subcutaneous injections in the belly

• Occasionally, a larger area of swelling around the injection site, though swelling typically reduces in less than 24 hours

  Serious Injection Site Reactions

A fluctuant (moveable), raised, red area that is exquisitely tender to touch with purulent (pus-like) discharge would warrant further medical evaluation. This should be compared to a simple nodule.

Systemic reactions include but are not limited to:

• Excessive swelling and redness

• Fever and signs of infection

• Chills and night sweats

• Feelings of fatigue or lethargy

• Shortness of breath

These symptoms warrant immediate medical care.

The potential complications of an injection may include an abscess, the development of cellulitis, or allergic responses.

When to Seek Immediate Medical Help

Patients experiencing any of the red-flag symptoms discussed should seek further consultation. Those experiencing non-improving symptoms for more than 24 hours should contact their healthcare provider. For issues like infections or large local reactions that appear like cellulitis, patients should contact 911 or seek otherwise urgent medical care.

How to Tell the Difference Between Similar Reactions

Some injection site reactions are similar, so we'll take this section to help describe the differences.

Cellulitis vs. Large Local Site Reactions

These are sometimes mistaken for one another. Large reactions typically result in a mild fever, do not cause tender lymph nodes, have no systemic toxicity, and resolve within a week. Cellulitis, on the other hand, typically results in fevers, lethargy, increasing skin tenderness with spreading redness, and may require antibiotics.

Allergic Reactions vs. Irritant Responses

Sometimes allergic reactions and irritant responses are also similar. Allergic reactions typically occur immediately after an injection and may have broader symptoms such as hives, whereas irritants typically have no systemic involvement, improve quickly, and are localized.

Tips for Avoiding Injection Site Reactions

Here are a few ways to help avoid any serious reactions:

• Get blood work done beforehand to check for allergies, and ensure that you are only injecting substances that are prescribed by a doctor and under the supervision of a healthcare professional.

• Be sure to use alcohol swabs or other cleansing measures discussed by your provider both before and after injections. A shower does not create a sterile injection field. A new swab should be used both before and after an injection and be allowed to completely dry before the injection is completed.

• Rotate injection sites as much as possible. This allows the skin from the previous injection to fully recover.

• Apply a cool compress for relief, and use proper technique.

• In some cases, antihistamines or pain relievers may be recommended to have on hand for mild cases.

TRT With Lucidity Health 

To conclude, most injection sites are mild, but it’s important to take action when it appears that an adverse event may have taken place. 

Lucidity Health provides TRT subscription plans as well as an exclusive peptide club for a variety of different types of optimization therapies. The first step towards TRT is to have your blood work done, so an experienced professional can analyze your labs. 

We encourage potential patients to reach out for more information or to see how we can help.