<unk>  is a prodrug of<unk> , and hence is an agonist of the androgen receptor, the biological target of endogenous androgens like<unk>  and dihydrotestosterone. It produces both androgenic and anabolic effects, as well as weak estrogenic effects due to metabolism of<unk>  into estradiol. In contrast to most other<unk>  esters, which are used as amorphous oil solutions,<unk>  is provided in the form of a microcrystalline aqueous suspension. It has very low water solubility and forms a long-lasting microcrystalline depot within muscle upon intramuscular injection. This respository slowly dissolves over time. As a result,<unk>  has a prolonged duration of action of approximately 2 weeks. It is administered at intervals of once every 1 to 2 weeks in men. Microcrystalline<unk>  in aqueous suspension requires a larger needle (21 gauge) than oil solutions due to the presence of solid crystals in the suspension. It can produce local irritation, pain, and redness upon injection.
Testosterone isobutyrate
Testosterone phenylacetate
Testosterone nicotinate
Testosterone hexahydrobenzoate
Estradiol butyrylacetate
Estradiol propoxyphenylpropionate
Estradiol dibutyrate
Testosterone cyclohexylpropionate