ZARAH- drospirenone and ethinyl estradiol
Watson Pharma, Inc.
PATIENTS SHOULD BE COUNSELED THAT THIS PRODUCT DOES NOT PROTECT AGAINST HIV INFECTION (AIDS) AND OTHER SEXUALLY TRANSMITTED DISEASES.
DESCRIPTION
ZARAH� (Drospirenone and ethinyl estradiol tablets) provides an oral contraceptive regimen consisting of 21 active tablets each containing 3 mg of drospirenone and 0.030 mg of ethinyl estradiol and 7 inert tablets. The inactive ingredients are lactose monohydrate, corn starch, pregelatinized starch, magnesium stearate, Vitamin E, FD&C Blue #1 Aluminum Lake. The inert tablets contain lactose anhydrous, microcrystalline cellulose, FD&C Yellow #6 Aluminum Lake and magnesium stearate.
Drospirenone (6R,7R,8R,9S,10R,13S,14S,15S,16S,17S)-1,3',4',6,6a,7,8,9,10,11,12,13,14,15,15a,16-hexadecahydro-10,13-dimethylspiro-[17H-dicyclopropa-6,7:15,16]cyclopenta[a]phenanthrene-17,2'(5H)-furan]-3,5'(2H)-dione) is a synthetic progestational compound and has a molecular weight of 366.5 and a molecular formula of C24 H30 O3 . Ethinyl estradiol (19-nor-17α-pregna 1,3,5(10)-triene-20-yne-3,17-diol) is a synthetic estrogenic compound and has a molecular weight of 296.4 and a molecular formula of C20 H24 O2 .
CLINICAL PHARMACOLOGY
Pharmacodynamics
Combination oral contraceptives (COCs) act by suppression of gonadotropins. Although the primary mechanism of this action is inhibition of ovulation, other alterations include changes in the cervical mucus (which increases the difficulty of sperm entry into the uterus) and the endometrium (which reduces the likelihood of implantation).
Drospirenone is a spironolactone analogue with antimineralocorticoid activity. Preclinical studies in animals and in vitro have shown that drospirenone has no androgenic, estrogenic, glucocorticoid, and antiglucocorticoid activity. Preclinical studies in animals have also shown that drospirenone has antiandrogenic activity.
INDICATIONS AND USAGE
ZARAH (Drospirenone and ethinyl estradiol tablets) is indicated for the prevention of pregnancy in women who elect to use an oral contraceptive.
Oral contraceptives are highly effective. Table 2 lists the typical accidental pregnancy rates for users of combination oral contraceptives and other methods of contraception. The efficacy of these contraceptive methods, except sterilization, depends upon the reliability with which they are used. Correct and consistent use of methods can result in lower failure rates.