Testosterone undecanoate treats low testosterone levels in men by increasing circulating levels through synthetic supplementation. It is an androgen and anabolic steroid (AAS).

The medication comes in two forms, as an injectable solution for administration inside the muscles as an oral medication. The injectable version is called Aveed and the capsule version is called Andriol.

For best results, patients should follow their provider’s dosing recommendations. Patients typically start with injections of 50-400 mg or with oral capsules of 120 mg to 160 mg divided into twice-daily doses.



Testosterone undecanoate is androgen and anabolic steroid (AAS) that supports healthy testosterone levels in men. It is marketed under the brand name Aveed for the injectable version and under the brand name Andriol for the oral capsules. For injections, the initial dose is 750 mg for adults followed by another 750 mg injection after four weeks and additional 750 mg injections every ten weeks after that.

All forms of testosterone therapy carry specific warnings regarding potential side effects. Some TRT types have possible reactions that are specific to those medications, such as increased cross-contamination risk with transdermal testosterone gels and patches. Before we discuss the most common side effects of testosterone therapy, we want to address testosterone undecanoate in particular and its risks.

Testosterone undecanoate risks and safety information:

  • Serious risk of pulmonary oil microembolism (POME) reactions which can include:
    • Throat tightening
    • Urge to cough
    • Chest pain
    • Dyspnea
    • Syncope
    • Dizziness
  • Anaphylaxis, including life-threatening reactions
  • Due to these risks, testosterone undecanoate injections are only available in a healthcare setting where the patient must remain for thirty minutes post-treatment to ensure there are no adverse reactions.
  • AVEED® is only available through a Risk Evaluation and Mitigation Strategy (REMS) program by doctors who have been specially trained to administer this medication.
  • Injection site reactions are also possible, including:
    • Redness
    • Swelling
    • Pain
    • Inflammation
    • Irritation
    • Itching

Testosterone treatment general side effects:

  • Acne
  • Oily skin
  • Elevated estrogen levels
  • Weight changes
  • Male breast tissue enlargement (gynecomastia)
  • Fatigue
  • Irritability
  • Increased hemoglobin
  • Mood swings
  • Erectile changes
  • Nausea or vomiting
  • Headache
  • Changes in skin color
  • Decreased or increased sex drive
  • Differences in hair growth – facial, body, and head
  • Depression
  • Irregular heartbeat

When properly prescribed and used, other forms of testosterone therapy rarely present a risk of side effects. The most common issues with testosterone cypionate and enanthate injections are injection site reactions. Transdermal testosterone gels and patches can cause skin irritation, rash, itching, and increase cross-contamination risk. Transbuccal testosterone tablets can alter taste and lead to gum sensitivity and pain.

As with other forms of testosterone replacement therapy (TRT), testosterone undecanoate (TU) is used to treat the symptoms associated with testosterone deficiency. The term given to natural testosterone production is endogenous testosterone, meaning derived from the male testes – more specifically, the Leydig cells. Exogenous testosterone, such as testosterone undecanoate, enters the bloodstream from external sources as a means to boost low testosterone levels.

Unlike other types of TRT administered at home, testosterone undecanoate (AVEED®), is a complex therapy that can only be administered in a medical setting such as a doctor’s office. Your doctor will prescribe testosterone undecanoate only if he or she feels that is the best treatment option for your needs.

Why do testosterone undecanoate injections need to be administered in a doctor’s office or another medical setting?

As we will discuss in the next section, there are multiple dangers associated with testosterone undecanoate usage that are not present with other types of TRT. For that reason, medical supervision is necessary for thirty minutes following the administration of the medication.

Can women use testosterone undecanoate for their low testosterone levels?

No, the dosage of AVEED® is far too high for female use. Testosterone undecanoate is only for males over age 18. It should not be used for illegal purposes such as bodybuilding or athletic enhancement. The only people who should receive TU for approved medical uses are men with verified testosterone deficiency.

Do I Need Prescription to Buy Testosterone Undecanoate?

As with all forms of TRT, testosterone undecanoate requires a prescription from a hormone specialist. However, you will not receive a prescription allowing you to purchase TU online or from a local pharmacy. Only a specially trained doctor who is part of the AVEED® REMS program can order testosterone undecanoate.

For most men looking to buy TU, this medication is NOT covered under most insurance policies. In some circumstances, a provider may cover treatment with testosterone undecanoate, and if that is so, there is an AVEED® Copay Assistance Program that can sometimes help with the out-of-pocket expense. The price of testosterone undecanoate is significantly higher than more traditional and preferred forms of injectable testosterone, such as testosterone cypionate and testosterone undecanoate, which you can get for sale with a doctor’s prescription.

Our hormone specialists do not prescribe testosterone undecanoate as they believe there are much better, safer, and less expensive alternatives to this treatment.

What is testosterone undecanoate, and how does it work?

Testosterone undecanoate is a long-lasting form of injectable testosterone administered only in a medical setting. It is not available for home use due to a higher risk of potential side effects. Supplemental testosterone therapy works by providing the body with an increased amount of testosterone for use by the androgen receptors.

Is Testosterone Undecanoate effective?

Testing has shown testosterone undecanoate to be as effective as other forms of testosterone therapy.

Where is the best place to inject testosterone undecanoate?

Because of the medical setting administration, testosterone undecanoate is injected into the buttocks. Other forms of testosterone therapy, such as testosterone cypionate and enanthate injections, can be administered to the thigh during at-home use.

Can testosterone undecanoate be prescribed online?

No, a doctor will not prescribe testosterone undecanoate online. You will need to visit a specialist in the office who is part of the AVEED® REMS program.

Is it legal to buy testosterone undecanoate online in the USA?

No, it is illegal to purchase testosterone undecanoate online in the US. The high-risk factors associated with this medication render it available only by doctor prescription and administered in a medical setting.

How do I buy testosterone undecanoate and not be scammed?

The purchase of testosterone undecanoate can only be made through a participating program physician. Any attempt to buy this medication in other ways opens the door to significant risks.

What are the better options for testosterone undecanoate treatment?

Due to the higher risks and costs associated with testosterone undecanoate, our doctors do not recommend this treatment. Instead, men who receive a diagnosis of testosterone deficiency are typically prescribed either testosterone cypionate, testosterone enanthate, or a combination of the two for at-home use. There is no need to pay higher costs associated with a more dangerous medication when self-administration of weekly testosterone injections is available at home.