Trade Names:Implanon- Implant 68 mg
Suppresses ovulation, increases viscosity of the cervical mucus, and alters the endometrium.
Bioavailability is approximately 100%. Mean C max ranges from 781 to 894 pg/mL and is reached within a few weeks after insertion. Concentration decreases gradually over time to 156 to 177 pg/mL at 36 mo.
Vd averages 201 L. 66% bound to plasma albumin.
Etonogestrel is metabolized in the liver by CYP3A4.
Elimination t ½ is approximately 25 h. Etonogestrel is excreted mainly in the urine as conjugates. After removal of the implant, concentrations decrease below assay sensitivity by 1 wk.
Prevention of pregnancy.
Male contraceptive agent.
Known or suspected pregnancy; current or past history of thrombosis or thromboembolic disorders; hepatic tumors or active liver disease; undiagnosed abnormal genital bleeding; known or suspected carcinoma of the breast or personal history of breast cancer; hypersensitivity to any component of the product.
Subdermal implant Insertion and removal of the etonogestrel implant are performed by a health care provider. The implant contains etonogestrel 68 mg and provides reversible contraception for up to 3 yr.
Store at 59° to 86°F. Protect from light.
Breakthrough bleeding or unintended pregnancy may occur. Consider use of an additional nonhormonal contraceptive method.Itraconazole, ketoconazole
Plasma hormone levels may be increased.Protease inhibitors (eg, ritonavir)
Safety and efficacy of oral contraceptives may be affected.
Sex hormone–binding globulin may be decreased for the first 6 mo after etonogestrel insertion, followed by gradual recovery; initially, thyroxine concentrations may be decreased slightly, followed by gradual recovery.
Hypertension, migraine, varicose vein (less than 5%).
Headache (25%); dizziness (7%); depression, emotional lability, nervousness (6%); abnormal crying, anxiety, asthenia, decreased libido, fatigue, hypoesthesia, insomnia, somnolence (less than 5%).
Acne (14%); pruritus, rash (less than 5%).
Pharyngitis (10%); abnormal vision, otitis media, rhinitis (less than 5%).
Abdominal pain (11%); nausea (6%); anorexia, constipation, diarrhea, dyspepsia, flatulence, gastritis, vomiting (less than 5%).
Vaginitis (14%); breast pain (13%); leukorrhea (10%); dysmenorrhea (7%); abnormal sexual function, breast discharge, breast enlargement, breast fibroadenosis, dysuria, genital pruritus, nonpuerperal lactation, ovarian cyst, pelvic cramping, positive cervical smear test, premenstrual cramping, vaginal discomfort (less than 5%).
Bleeding irregularities (11%).
Injection-site reaction, insertion-site pain (5%).
Increased weight (14%); decreased weight (less than 5%).
Back pain (7%); arthralgia, myalgia, skeletal pain (less than 5%).
Upper respiratory tract infection (13%); sinusitis (6%); asthma, coughing (less than 5%).
Influenza-like symptoms (8%); pain (6%); allergic reaction, edema, fever, generalized edema, hot flushes, increased appetite (less than 5%).
Perform a complete medical evaluation prior to implantation and carefully monitor women with a family history of breast cancer or those who have breast nodules. Monitor women with diabetes or impaired glucose tolerance.
Not indicated for use during pregnancy.
Small amounts excreted in breast milk. May be used during lactation after postpartum wk 4.
Safety and efficacy not established.
Etonogestrel may be metabolized poorly. If jaundice develops, etonogestrel may be poorly metabolized.
Changes in vaginal bleeding pattern may occur.
Consider ophthalmologic examination in contact lens wearers who develop visual changes or lens intolerance.
Women with breast cancer should not use hormonal contraceptives because breast cancer may be hormonally sensitive.
Carefully observe patients with a history of depression. If patients become severely depressed, consider removing the implant.
Be alert for ectopic pregnancy after insertion.
Because steroid contraceptives cause some degree of fluid retention, use them with caution in patients with conditions that may be aggravated by fluid retention.
The risk of gallbladder disease may be increased slightly.
Benign hepatic adenomas have been associated with use of combined oral contraceptives.
Incidence of hypertension increases with increasing doses of progestin.
Mild insulin resistance and small changes in glucose concentrations may occur.
Atresia of the follicle may be delayed and follicle may continue to grow beyond the size attained in a normal cycle.
Cigarette smoking increases the risk of serious CVP adverse reactions from use of combined hormonal contraceptives. It is not known if a similar risk exists with progestin-only methods.
Serious thromboembolic reactions have been reported, including cases of fatal pulmonary emboli.
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