The following serious adverse reactions with the use of COCs are discussed elsewhere in the labeling:

• Serious cardiovascular events and smoking [see BOXED WARNING and WARNINGS AND PRECAUTIONS]
• Vascular events [see WARNINGS AND PRECAUTIONS]
• Liver disease [see WARNINGS AND PRECAUTIONS]

Adverse reactions commonly reported by COC users are:

• Irregular uterine bleeding
• Nausea
• Breast tenderness
• Headache

Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to the rates in the clinical trials of another drug and may not reflect the rates observed in practice.

The clinical trial that evaluated the safety and efficacy of Seasonique (levonorgestrel, ethinyl estradiol) was a 12-month, randomized, multicenter, open-label study, which enrolled women aged 18-40, of whom 1,006 took at least one dose of Seasonique (levonorgestrel, ethinyl estradiol) .

Adverse Reactions Leading to Study Discontinuation: 16.3% of the women discontinued from the clinical trial due to an adverse reaction; the most common adverse reactions (≥ 1% of women) leading to discontinuation were irregular and/or heavy uterine bleeding (5.9%), weight gain (2.4%), mood changes (1.5%), and acne (1.0%).

Common Treatment-Emergent Adverse Reactions (≥ 5% of women):

irregular and/or heavy uterine bleeding (17%), weight gain (5%), acne (5%).

Serious Adverse Reactions: migraine, cholecystitis, cholelithiasis, pancreatitis, abdominal pain, and major depressive disorder.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Seasonique (levonorgestrel, ethinyl estradiol) . Because these reactions are reported voluntarily from a population of uncertain size, it is not possible to reliably estimate their frequency of establish a causal relationship to drug exposure.

Gastrointestinal disorders: abdominal distension, vomiting

General disorders and administration site conditions: chest pain, fatigue, malaise, edema peripheral, pain

Immune system disorders: hypersensitivity reaction

Investigations: blood pressure increased

Musculoskeletal and connective tissue disorders: muscle spasms, pain in extremity

Nervous system disorders: dizziness, loss of consciousness

Psychiatric disorders: insomnia

Reproductive and breast disorders: dysmenorrhea

Respiratory, thoracic and mediastinal disorders: pulmonary embolism, pulmonary thrombosis

Skin and subcutaneous tissue disorders: alopecia

Vascular disorders: thrombosis

Read the Seasonique (levonorgestrel, ethinyl estradiol) Side Effects Center for a complete guide to possible side effects »

No drug-drug interaction studies were conducted with Seasonique (levonorgestrel, ethinyl estradiol) .

Changes in Contraceptive Effectiveness Associated with Co-Administration of Other Products

If a woman on hormonal contraceptives takes a drug or herbal product that induces enzymes, including CYP3A4, that metabolize contraceptive hormones, counsel her to use additional contraception or a different method of contraception. Drugs or herbal products that induce such enzymes may decrease the plasma concentrations of contraceptive hormones, and may decrease the effectiveness of hormonal contraceptives or increase breakthrough bleeding. Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include:

• barbiturates
• bosentan
• carbamazepine
• felbamate
• griseofulvin
• oxcarbazepine
• phenytoin
• rifampin
• St. John's wort
• topiramate

HIV protease inhibitors and non-nucleoside reverse transcriptase inhibitors: Significant changes (increase or decrease) in the plasma levels of the estrogen and progestin have been noted in some cases of co-administration of HIV protease inhibitors or with non-nucleoside reverse transcriptase inhibitors.

Antibiotics: There have been reports of pregnancy while taking hormonal contraceptives and antibiotics, but clinical pharmacokinetic studies have not shown consistent effects of antibiotics on plasma concentrations of synthetic steroids.

Consult the labeling of all concurrently-used drugs to obtain further information about interactions with hormonal contraceptives or the potential for enzyme alterations.

Increase in Plasma Levels of Estradiol Associated with Co-Administered Drugs

Co-administration of atorvastatin and certain COCs containing ethinyl estradiol increase AUC values for ethinyl estradiol by approximately 20%. Ascorbic acid and acetaminophen may increase plasma ethinyl estradiol levels, possibly by inhibition of conjugation. CYP3A4 inhibitors such as itraconazole or ketoconazole may increase plasma hormone levels.

Changes in Plasma Levels of Co-Administered Drugs

COCs containing some synthetic estrogens (e.g., ethinyl estradiol) may inhibit the metabolism of other compounds. COCs have been shown to significantly decrease plasma concentrations of lamotrigine likely due to induction of lamotrigine glucuronidation. This may reduce seizure control; therefore, dosage adjustments of lamotrigine may be necessary. Consult the labeling of the concurrently-used drug to obtain further information about interactions with COCs or the potential for enzyme alterations.

Last reviewed on RxList: 8/30/2010
This monograph has been modified to include the generic and brand name in many instances.