Drug interactions -summary-

+ Etonogestral-

Anticonvulsants - carbamazepine, oxacarbamazepine, topiramine-
anticonvulsants may increase metabolism of contraceptives leading to decreased
efficacy and possible unitended pregnancy

Antifungals- griesofluvin, ketoconazole, itraconazole-
contrceptive eficacy reduced when coadministered with griseofluvin .
Itraconazole and ketoconazole may increase plasma hormone levels

Barbiturates - butabital, phenobarbital, secobarbital -
barbiturates induce progestin metabolism ( CYP3A4 ) and increase sex hormone binding
globulin synthesis  reducing progestin concentrations

Hydantoins- fosphenytoin, phenytoin-
hydantoin induce progestin metabolism CYP3A4 and increase sex hormone binding globulin
synthesis reducing progestin concentrations

Protease  inhibitors eg atazanavir , retonivir-
increase and decrease AUC of progestin noted when hormonal contraceptives are coadministered
with protease inhibitors

Rifamycin eg  rifampin, rifabutin-
rifamycin may induce metabolism of progestin CYP3A4 leading to decreased efficacy of hormonal
contraceptives

St. Johns wort -
St Johns wort may induce hepatic enzymes and reduce efficacy of contraceptives

Etonogestral + lamotigine-
hormonal contraceptive may increase lamotrigine metabolism decreasing the therapeutic
effect

Etonogestral + Selegine-
hormonal contraceptives inhibit the metabolism of selegiline increasing risk of adverse reactions

Contraception

Adverse reactions leading to discontinuation-

CNS-         depression 1%     emotional lability  2%   headache    1%

Dermatologic-   acne   1%

GU-     bleeding irregularites  10%

Miscellaneous-     weight increase  2%

Adverse reactions-

CNS-        depression  5%     dizziness 7%   emotional lability  6%    headache    23%
                 nervousness 5%   

Dermatologic-    acne  13% 

GI-          abdominal pain    10%       nausea  6%

GU -      breast pain 12%         dysmenorrhea   7%   leukorrhea   9%    vaginitis    14%

Musculoskeletal -    back pain  6% 

Respiratory-    pharyngitis   10%    sinusitis    5%    upper respiratory tract infection 12%

Miscellaneous-     influenza like symptoms   7%   insertion site pain 5%    pain   5%
                                weight increase   13%    

Do not use in women who have known or suspected pregnancy, current or past history of
thrombosis or thromboembolic disorders, hepatic tumors, ( benign or malignant ) or
active liver disease, undiagnosed genital bleeding, known or suspected carcinoma of the
breast or personal history of breast cancer or hypersensitivity to any of the components of
etonogestral implant.

Special precautions-
Complications of insertion or removal- insert the implant subdermally so that it is palpable
after insertion.Undetected failure to insert implant may lead to unintended pregnancy

Etopic pregnancy- be alert to the possibility of an ectopic pregnancy among patients using
etonegestral implant

Bleeding irregularites- patients who use the implant are likely to have changes in their vaginal
bleeding patterns that are often unpreditable. This may include changes in bleeding frequency
or duration or amenorrohea

Cigeratte smoking- cigarette smoking increases risk of serious cardiovascular adverse reactions
The risk increases with age and heavy smoking

Elevated blood pressure- an increase in blood pressure has been reported in women taking
combination hormonal contraceptives. For most women elevated blood pressure will return
to normal after stoping hormonal contraceptives

Carcinoma of breast and reproductive organs- women with breast cancer should not use
hormonal contraceptives because breast cancer may be hormonally sensitive.

Depression- carefully evaluate women with a history of depression. Consider removing the
implant who become significantly depressed.

Pregnancy- the etonogestral implant is not indicated for use during pregnancy

Lactation- use of etongestral implant before the fourth postpartum week has not been studied

Children- safety and efficacy of implant have not been established in women of reproductive
age. Safety and efficacy are expected to be the same for postpubertal adolescents

Elderly- this product has not been studied in women older than 65 yeras of age and is not
indicated in this population.

Indication-
Contraception

Dosage-
Etonogestral implant is a long acting ( up to 3 years ) reversible contraceptive method

Insertion- all health care providers performing insertions and or removal of the implant must
receive instruction and training where appropiate , supervision prior to inserting or removing
 etonogestral implant.

The implant must be inserted by the expiration date stated on the packing. The implant must
be removed by the end of third year and may be replaced by a new implantat the time of
removal if continued contraception is required

Rule out pregnancy before inserting  the estongestral implant.

1. Counsel patients that the etonogestral does not protect against infection from HIV or sexually
    transmitted disceases.

2. The most common side effects of the implant is change in menstrual periods. Counsel patients
    that their menstrual period to be irregular and unpredictable through out the time they are
    using the implant

3.Warn patients that they may have more bleeding , less bleeding or no bleeding , that the
   time between periods may vary and in between they may have spotting.

4. Tell patients that must have the implant removed after 3 years  and that if they want to
    continue using the implant, a health care provider can put a new implant under their skin after
    taking out the old one. 

Pregnancy-
The etonogestral implant is not indicated for use during pregnancy

Lactation-
Use of etongestral implant before the fourth postpartum week has not been studied

Children-
Safety and efficacy of implant have not been established in women of reproductive
age. Safety and efficacy are expected to be the same for postpubertal adolescents

Elderly-
This product has not been studied in women older than 65 yeras of age and is not
indicated in this population.