CYP3A4 produces norcodeine, and UGT2B7 conjugates codeine, norcodeine, and morphine to the corresponding 3- and 6-glucuronides. Srinivasan, Wielbo and Tebbett speculate that codeine-6-glucuronide is responsible for a large percentage of the analgesia of codeine, and thus these patients should experience some analgesia. Many of the adverse effects will still be experienced in poor metabolizers. Conversely, between 0.5% and 2% of the population are "extensive metabolizers"; multiple copies of the gene for 2D6 produce high levels of CYP2D6 and will metabolize drugs through that pathway more quickly than others. Some medications are CYP2D6 inhibitors and reduce or even completely block the conversion of codeine to morphine. The best-known of these are two of the selective serotonin reuptake inhibitors, paroxetine (Paxil) and fluoxetine (Prozac) as well as the antihistamine diphenhydramine (Benadryl) and the antidepressant bupropion (Wellbutrin, also known as Zyban). Other drugs, such as rifampicin and dexamethasone, induce CYP450 isozymes and thus increase the conversion rate. CYP2D6 converts codeine into morphine, which then undergoes glucuronidation. Life-threatening intoxication, including respiratory depression requiring intubation, can develop over a matter of days in patients who have multiple functional alleles of CYP2D6, resulting in ultrarapid metabolism of opioids such as codeine into morphine.Studies on codeines analgesic effect are consistent with the idea that metabolism by CYP2D6 to morphine is important, but some studies show no major differences between those who are poor metabolizers and extensive metabolizers.
Ethinylestradiol/norethisterone acetate (EE/NETA), or ethinylestradiol/norethindrone acetate, is a combination of ethinylestradiol (EE) and norethisterone acetate (NETA) which is used as birth control and menopausal hormone therapy. EE is an estrogen, while norethisterone acetate (NETA) is a progestin. It is taken by mouth. Some preparations of EE/NETA used in birth control additionally contain an iron supplement in the form of ferrous fumarate.In 2019, it was the 42nd most commonly prescribed medication in the United States, with more than 16 million prescriptions. Society and culture
Brand names
Brand names of EE/NETA include Anovlar, Blisovi, Cumorit, Estrostep, FemHRT, Fyavolv, Gildess, Junel, Larin, Leribane, Loestrin, Lo Loestrin (Lo Lo), Mibelas, Microgestin, Minastrin, Norlestrin, Primodos, Taytulla, and Tri-Legest, among others.In addition, the combination is sold in the United States under the brand name FemHRT for use in menopausal hormone therapy. See also
Estradiol/norethisterone acetate
Oral contraceptive formulations
List of combined sex-hormonal preparations
Nand Peeters

References
External links
"Ethinyl estradiol mixture with norethindrone acetate". Drug Information Portal. U.S. National Library of Medicine.