For most folks, a regular injection (subcutaneous or intramuscular) will give a sufficiently-high, stable level enough to suppress the other primary sex hormone.
Commonly-available estradiol esters are valerate, cypionate & enanthate.
Commonly-available testosterone esters are cypionate, enanthate & undecanoate.
Such injections are ideal for monotherapy HRT (i.e., a sex hormone without medication that blocks the other sex hormone).
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