Mirena
IUD May Be Best for Heavy Menstrual Bleeding »
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Mirena
Mirena
(levonorgestrel-releasing) Intrauterine System
DRUG DESCRIPTION
Mirena (levonorgestrel-releasing intrauterine system) is intended to provide an initial release rate of 20 mcg/day of levonorgestrel
Levonorgestrel USP, (-)-13-Ethyl-17-hydroxy-18,19-dinor-17α-pregn-4-en-20-yn-3-one, the active ingredient in Mirena (levonorgestrel-releasing intrauterine system) , has a molecular weight of 312.4, a molecular formula of C21H28O2, and the following structural formula:
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Mirena
Mirena (levonorgestrel-releasing intrauterine system) consists of a T-shaped polyethylene frame (T-body) with a steroid reservoir (hormone elastomer core) around the vertical stem. The reservoir consists of a white or almost white cylinder, made of a mixture of levonorgestrel and silicone (polydimethylsiloxane), containing a total of 52 mg levonorgestrel. The reservoir is covered by a semi-opaque silicone (polydimethylsiloxane) membrane. The T-body is 32 mm in both the horizontal and vertical directions. The polyethylene of the T-body is compounded with barium sulfate, which makes it radiopaque. A monofilament brown polyethylene removal thread is attached to a loop at the end of the vertical stem of the T-body.
Schematic drawing of Mirena (levonorgestrel-releasing intrauterine system)
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Inserter
Mirena (levonorgestrel-releasing intrauterine system) is packaged sterile within an inserter. The inserter, which is used for insertion of Mirena (levonorgestrel-releasing intrauterine system) into the uterine cavity, consists of a symmetric two-sided body and slider that are integrated with flange, lock, pre-bent insertion tube and plunger. Once Mirena (levonorgestrel-releasing intrauterine system) is in place, the inserter is discarded.
Diagram of Inserter
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What are the possible side effects of levonorgestrel intrauterine system (Mirena)?
Get emergency medical help if you have severe pain in your lower stomach or side. This could be a sign of a tubal pregnancy (a pregnancy that implants in the fallopian tube instead of the uterus). A tubal pregnancy is a medical emergency.
The levonorgestrel intrauterine device may become embedded into the wall of the uterus, or may perforate (form a hole) in the uterus. If this occurs, the device may no longer prevent pregnancy, or it may move outside the uterus and cause scarring, infection, or damage to other organs. If the device embeds in or...
Read All Potential Side Effects and See Pictures of Mirena »
What are the precautions when taking levonorgestrel-releasing intrauterine system (Mirena)?
Before using this medication device, tell your doctor or pharmacist if you are allergic to levonorgestrel, or to any other progestins (e.g., norethindrone, desogestrel); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medication device should not be used if you have certain medical conditions. Before using this product, consult your doctor or pharmacist if you have: current known or suspected pregnancy, previous ectopic pregnancy, uterus problems (e.g., cancer, endometriosis, fibroids, pelvic inflammatory disease-PID), other IUD (intrauterine device) still in place, vaginal problems (e.g., infection), breast cancer, liver disease/tumors, any...
Last reviewed on RxList: 12/20/2010
This monograph has been modified to include the generic and brand name in many instances.
Additional Mirena Information
Mirena - User Reviews
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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