Effect on long-term treatment with norethisterone (a progestogen-only contraceptive) on adrenomedullary hormonal...

Effect of prolonged treatment of norethisterone (a progestogen-only contraceptive) was evaluated on adrenomedullary activity in albino rat. Administration of this synthetic steroidal contraceptive in a dosage of 0.5 mg/rat/day, consecutively for 75 days, raised the epinephrine level of the adrenal gland. No other perceptible change was marked in the medullary histology, mitotic incidence or in the norepinephrine level of the adrenal gland after the treatment. It is concluded that prolonged treatment with an even progestogen-only contraceptive, like norethisterone, causes untoward effect at least on adrenomedullary hormonal activity in the albino rat.