Implanon - General Information

Implanon is a molecule used in hormonal contraceptives, most notably the subdermal implant Implanon. [Wikipedia]


Pharmacology of Implanon

Implanon is used as a female contraceptive. Implanon is a progestin or a synthetic form of the naturally occurring female sex hormone, progesterone. In a woman's normal menstrual cycle, an egg matures and is released from the ovaries (ovulation). The ovary then produces progesterone, preventing the release of further eggs and priming the lining of the womb for a possible pregnancy. If pregnancy occurs, progesterone levels in the body remain high, maintaining the womb lining. If pregnancy does not occur, progesterone levels in the body fall, resulting in a menstrual period. Implanon tricks the body processes into thinking that ovulation has already occurred, by maintaining high levels of the synthetic progesterone. This prevents the release of eggs from the ovaries.


Implanon for patients


Implanon Interactions

Etonogestrel may interact with the following medications: acetaminophen (Tylenol), antibiotics such as ampicillin and tetracycline, anticonvulsants (Dilantin, Phenobarbital, Tegretol, Trileptal, Topamax, Felbatol), antifungals (Gris-PEG, Nizoral, Sporanox), atorvastatin (Lipitor), clofibrate (Atromid-S), cyclosporine (Neoral, Sandimmune), HIV drugs classified as protease inhibitors (Agenerase, Crixivan, Fortovase, Invirase, Kaletra, Norvir, Viracept), morphine (Astramorph, Kadian, MS Contin), phenylbutazone, prednisolone (Prelone), rifadin (rifampin), St. John's wort, temazepam, theophylline (Theo-Dur), and vitamin C.


Implanon Contraindications

Etonogestrel is contraindicated in the following: clotting disorder (past or present), tendency for strokes or mini-strokes (past or present), heart disease (past or present), heart valve disorder, severe high blood pressure, diabetes with impaired circulation, certain types of headaches, breast cancer (past or present), endometrial cancer or any other estrogen-dependent cancer, unexplained vaginal bleeding, liver disease or liver tumors, jaundice during pregnancy or from prior hormonal contraceptive use, pregnancy, smoking 15 or more cigarettes per day past age 35, planned surgery that will keep you immobilized, and allergy to etonogestrel.


Additional information about Implanon

Implanon Indication: For use as a female contraceptive (depot).
Mechanism Of Action: Implanon binds to the progesterone and estrogen receptors. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins like etonogestrel will slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH (luteinizing hormone) surge.
Drug Interactions: Not Available
Food Interactions: Avoid alcohol.
Take with food.
Avoid excessive quantities of coffee or tea (Caffeine).
Increase dietary intake of magnesium, folate, vitamin B6, B12, and/or consider taking a multivitamin.
Take at the same time everyday.
Generic Name: Etonogestrel
Synonyms: Not Available
Drug Category: Contraceptives
Drug Type: Small Molecule; Approved; Investigational

Other Brand Names containing Etonogestrel: Implanon;
Absorption: Not Available
Toxicity (Overdose): Symptoms of overdose include nausea, vomiting, vaginal bleeding, and other menstrual irregularities.
Protein Binding: Not Available
Biotransformation: Hepatic.
Half Life: 25 hours
Dosage Forms of Implanon: Implant Transdermal
Chemical IUPAC Name: (17R)-13-ethyl-17-ethynyl-17-hydroxy-11-methylidene-2,6,7,8,9,10,12,14,15,16-decahydro-1H-cyclopenta[a]phenanthren-3-one
Chemical Formula: C22H28O2
Etonogestrel on Wikipedia:
Organisms Affected: Humans and other mammals