SteroidTestosterone

Testosterone Undecanoate

Testosterone ester (very long-acting; oral & injectable)

Also known as Aveed, Nebido, test U, testosterone

Half-life

~20-34 days

What is Testosterone Undecanoate?

Ultra long ester (14-week half-life). Requires only 4x/year injections. Used in Aveed/Nebido TRT.

How Testosterone Undecanoate works

Androgen receptor agonist ester releasing testosterone slowly from oil depot for long-interval TRT.

Benefits & uses

Very long-acting testosterone
Infrequent dosing (injectable) / oral option
TRT convenience

Common uses: TRT (convenience dosing), stable testosterone levels with minimal injections.

Testosterone Undecanoate dosage

Protokol doesn't recommend doses for prescription or controlled compounds. Any figures below are reference or observational reports — dosing should be set with a qualified clinician.

Commonly reported: TRT dosing at long intervals (observational)Observational use reports — not a recommendation.

Testosterone Undecanoate half-life

~20-34 days (IM depot)

Testosterone Undecanoate side effects

Pulmonary oil microembolism risk. Less flexible dosing.

Erythrocytosis
Acne/androgenic effects
Blood pressure and lipid changes
HPTA suppression
Estrogen rise
Acne
Raised hematocrit
Lipid shift

Warnings & monitoring

Requires bloodwork + medical monitoring
Injectable form: rare cough/reaction at injection reported
Aromatizes

Track Testosterone Undecanoate in Protokol.

Log doses, model half-lives, check interactions, and line it all up against your bloodwork. Free on iPhone and Android.