DƯỢC LÍ Goodman & Gilman's The Pharmacological Basis of Therapeutics 12th, 2010

Table 66–2
Brand Names and Formulations of Oral Contraceptives (Continued)
PRODUCT
BRAND NAME a
Combination estrophasic Estrogen (μg) Progestin (mg)
Ethinyl estradiol/norethindrone ESTROSTEP 20 1 (5 tabs)
30 1 (7 tabs)
35 1 (9 tabs)
Combination extended cycle Estrogen (μg) Progestin (mg)
Ethinyl estradiol/drospirenone YAZ 20 3 (24 tabs)
Ethinyl estradiol/levonorgesterol LYBREL 20 0.09 (28 tabs)
SEASONALE 30 0.15 (84 tabs)
SEASONIQUE 30 0.15 (84 tabs)
10 — (7 tabs)
Ethinyl estradiol/norethindrone LOESTRIN 24 20 1 (24 tabs)
Progestin only Estrogen (μg) Progestin (mg)
Norethindrone MICRONOR — 0.35 c
NOR-QD — 0.35 c
Norgestrel OVRETTE — 0.075 c
Emergency contraception
Levonorgestrel PLAN B — 0.75 2 doses
Ulipristal ella; ellaOne — 30 mg 1 dose
(progesterone partial agonist)
Unless otherwise indicated, the products are packaged with 21 active (hormone-containing) pills and 7 placebo tablets. For formulations that differ
from this standard (e.g., multiphasic pills, extended-cycle formulations), the numbers of tablets of each pill strength are indicated. a Some formulations
also contain iron to diminish the risk of Fe-deficiency anemia; these are not listed separately here. b Combination formulations contain both an
estrogen and a progestin. c Denotes continuous administration of active pills.
Progestin-Only Contraceptives. Progestin-only minipills
contain derivatives of 17α-alkyl-19-nortestosterone
but do not contain an estrogen. Although they do inhibit
ovulation to some degree, their efficacy also reflects
changes in the cervical mucus that inhibit fertilization
and endometrial changes that inhibit implantation. They
are slightly less effective than the combination estrogen/
progestin formulations, particularly when doses are
missed or the pill is taken at different times of the day,
but provide an alternative in settings where estrogencontaining
formulations are contraindicated. Their major
adverse effect is breakthrough bleeding.
Progestins also are used for long-acting contraception.
A depot formulation of medroxyprogesterone
(DEPO-PROVERA) injected subcutaneously or intramuscularly
provides effective contraception for 3 months.
Its use has been associated with decreased bone mineral
density, as noted by a black box warning in the
product label. Teenagers and younger women who
have not achieved maximal bone density may be particularly
at risk, although the data suggest that bone
density returns to pretreatment levels fairly quickly
after drug cessation. Subdermal implants of progestinimpregnated
rods provide effective contraception over
several years. The only implant system currently
approved in the U.S. is IMPLANON, which incorporates
3-ketodesogestrel, an active metabolite of desogestrel,
into an inert matrix. The progestin is released slowly
from the matrix to maintain a serum concentration
considerably higher than that needed to suppress ovulation
for 3 years. In most women, progestin concentrations
are undetectable 1 week after surgical removal
of the implant, and ovulation occurs within 6 weeks.
Intermittent breakthrough bleeding is the major undesirable
effect; acne or weight gain also may occur.
An intrauterine device that releases levonorgestrel (MIRENA)
provides highly effective contraception for up to 5 years. It achieves
local progestin concentrations that are ~1000-fold higher than systemic
levels and is thought to act predominantly to inhibit gamete
function and survival via local changes in the cervical mucus. This
medical device also is undergoing evaluation for other indications
such as menorrhagia, endometriosis, and endometrial protection in
menopausal women receiving estrogens (Mansour, 2007; see
“Endometriosis”).