[6] Side effects of NETA include menstrual irregularities, headaches, nausea, breast tenderness, mood changes, acne, increased hair growth, and others.

[16][4] Transdermal patches providing a combination of 50 μg/day estradiol and 0.14 or 0.25 mg/day NETA are available under the brand names CombiPatch and Estalis.

[17][18][19][20] Side effects of NETA include menstrual irregularities, headaches, nausea, breast tenderness, mood changes, acne, increased hair growth, and others.

[9] Upon oral ingestion, it is rapidly converted into norethisterone by esterases during intestinal and first-pass hepatic metabolism.

[10] Hence, as a prodrug of norethisterone, NETA has essentially the same effects, acting as a potent progestogen with additional weak androgenic and estrogenic activity (the latter via its metabolite ethinylestradiol).

[26] Generation of ethinylestradiol with high doses of NETA may increase the risk of venous thromboembolism but may also decrease menstrual bleeding relative to progestogen exposure alone.

[27][28] NETA has antigonadotropic effects via its progestogenic activity and can dose-dependently suppress gonadotropin and sex hormone levels in women and men.

[1] In healthy young men, NETA alone at a dose of 5 to 10 mg/day orally for 2 weeks suppressed testosterone levels from ~527 ng/dL to ~231 ng/dL (–56%).

[2][5][4] NETA is marketed in high-dose 5 mg oral tablets in the United States under the brand names Aygestin and Norlutate for the treatment of gynecological disorders.