"May 23, 2012 -- Women using birth control pills may have a 20 times greater risk of an unplanned pregnancy than women using longer-acting forms of birth control like an intrauterine device (IUD) or implant, new research shows.
The following serious or otherwise important adverse reactions are discussed in elsewhere in the labeling:
- Ectopic Pregnancy [see WARNINGS AND PRECAUTIONS]
- Intrauterine Pregnancy [see WARNINGS AND PRECAUTIONS]
- Group A Streptococcal Sepsis (GAS) [see WARNINGS AND PRECAUTIONS]
- Pelvic Inflammatory Disease [see WARNINGS AND PRECAUTIONS]
- Alterations of Bleeding Patterns [see WARNINGS AND PRECAUTIONS]
- Perforation [see WARNINGS AND PRECAUTIONS]
- Expulsion [see WARNINGS AND PRECAUTIONS]
- Ovarian Cysts [see WARNINGS AND PRECAUTIONS]
Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The data provided reflect the experience with the use of Mirena in the adequate and well-controlled studies as well as in the supportive and uncontrolled studies for contraception and heavy menstrual bleeding (n=5,091). The data cover more than 12,101 women-years of exposure, mainly in the contraception studies (11,761 women-years). The frequencies of reported adverse drug reactions represent crude incidences.
The most common adverse reactions ( ≥ 10% users) are alterations of menstrual bleeding patterns [including unscheduled uterine bleeding (31.9%), decreased uterine bleeding (23.4%), increased scheduled uterine bleeding (11.9%), and female genital tract bleeding (3.5%)], abdominal/pelvic pain (22.6%), amenorrhea (18.4%), headache/migraine (16.3%), genital discharge (14.9%), and vulvovaginitis (10.5%). Adverse reactions reported in ≥ 5% of users are shown in Table 1.
Table 1 : Adverse Reactions ≥ 5% Reported in
Clinical Trials with Mirena
|System Organ Class||Adverse Reactions||% (N= 5,091)|
|Reproductive system and breast disorders||alteration of menstrual bleeding pattern, including:|
|unscheduled uterine bleeding||31.9|
|decreased uterine bleeding||23.4|
|increased scheduled uterine bleeding||11.9|
|female genital tract bleeding||3.5|
|benign ovarian cyst and associated complications||7.5|
|Gastrointestinal disorders||abdominal/pelvic pain||22.6|
|Nervous system disorders||headache/migraine||16.3|
|Musculoskeletal and connective tissue disorders||back pain||7.9|
|Skin and subcutaneous tissue disorders||acne||6.8|
|Psychiatric disorders||depression/depressive mood||6.4|
The following adverse reactions have been identified during post approval use of Mirena. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
- Arterial thrombotic and venous thromboembolic events, including cases of pulmonary emboli, deep vein thrombosis and stroke
- Device breakage
- Hypersensitivity (including rash, urticaria and angioedema)
- Increased blood pressure
Read the Mirena (levonorgestrel-releasing intrauterine system) Side Effects Center for a complete guide to possible side effects
No drug-drug interaction studies have been conducted with Mirena.
Drugs or herbal products that induce enzymes, including CYP3A4, that metabolize progestins may decrease the serum concentrations of progestins.
Some drugs or herbal products that may decrease the serum concentration of LNG include:
- St. John's wort
Significant changes (increase or decrease) in the serum concentrations of the progestin have been noted in some cases of co-administration with HIV protease inhibitors or with non-nucleoside reverse transcriptase inhibitors. CYP3A4 inhibitors such as itraconazole or ketoconazole may increase plasma hormone levels.
Consult the labeling of all concurrently used drugs to obtain further information about interactions with Mirena or the potential for enzyme alterations.This monograph has been modified to include the generic and brand name in many instances.
Last reviewed on RxList: 3/15/2017
Additional Mirena Information
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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