Drug Guide
Elagolix Sodium, Estradiol, Norethindrone Acetate
Classification
Therapeutic: Hormonal therapy for endometriosis-associated pain
Pharmacological: GnRH receptor antagonist with combined estrogen/progestin therapy
FDA Approved Indications
- Treatment of moderate to severe pain associated with endometriosis in women who wish to retain their fertility
Mechanism of Action
Elagolix is a gonadotropin-releasing hormone (GnRH) receptor antagonist that reduces ovarian estrogen production. Estradiol (estrogen) and norethindrone acetate (progestin) are used to mitigate hypoestrogenic side effects and provide hormone replacement, maintaining hormonal balance during treatment.
Dosage and Administration
Adult: Oriahnn is administered as a daily oral dose, typically consisting of elagolix, estradiol, and norethindrone acetate in a co-packaged formulation, as directed by the healthcare provider.
Pediatric: Not indicated for pediatric use.
Geriatric: Limited data; caution advised as with other hormonal therapies.
Renal Impairment: Adjustments not specified; use with caution.
Hepatic Impairment: Use with caution; dose adjustment may be needed given hepatic metabolism of components.
Pharmacokinetics
Absorption: Rapid absorption after oral administration.
Distribution: Widely distributed; highly bound to plasma proteins.
Metabolism: Metabolized hepatically via CYP enzymes for elagolix; estradiol and norethindrone acetate undergo hepatic metabolism.
Excretion: Elagolix and metabolites excreted primarily via feces and urine.
Half Life: Elagolix: approximately 1 to 4 hours; estradiol and norethindrone acetate have longer half-lives, around 13 hours and 8 hours respectively.
Contraindications
- Pregnancy
- Undiagnosed genital bleeding
- Known or suspected hormone-sensitive cancers
- History of thromboembolic disorders
Precautions
- Assess for liver dysfunction, osteoporosis risk, cardiovascular health, and contraindications before initiation.
Adverse Reactions - Common
- Hot flashes (Common)
- Headache (Common)
- Nausea (Common)
- Vaginal bleeding (Common)
Adverse Reactions - Serious
- Thromboembolic events (Rare but serious)
- Liver injury (Rare)
- Bone mineral density loss (Potential with prolonged use)
Drug-Drug Interactions
- CYP3A4 inhibitors or inducers may alter elagolix levels.
Drug-Food Interactions
- Food does not significantly affect absorption.
Drug-Herb Interactions
- Caution with herbal supplements that affect hepatic enzymes or coagulation.
Nursing Implications
Assessment: Monitor for efficacy, side effects, signs of thromboembolism, liver function, and bone health.
Diagnoses:
- Pain related to endometriosis; Risk for osteoporosis; Risk for thromboembolic events.
Implementation: Administer as prescribed, assess menstrual bleeding, monitor liver enzymes and BMD if indicated.
Evaluation: Evaluate pain relief, monitor for side effects, and assess adherence.
Patient/Family Teaching
- Take medication as directed, do not skip doses.
- Report symptoms of blood clots, severe headache, visual changes, or abnormal bleeding.
- Attend regular follow-up appointments for monitoring.
- Use additional contraceptive measures if pregnancy is not desired.
Special Considerations
Black Box Warnings:
- Risk of serious adverse cardiovascular and thromboembolic events with hormonal therapies.
Genetic Factors: None specified.
Lab Test Interference: May alter certain hormone or liver function tests.
Overdose Management
Signs/Symptoms: Nausea, vomiting, dizziness, fatigue.
Treatment: Supportive care; no specific antidote; seek immediate medical attention.
Storage and Handling
Storage: Store at controlled room temperature away from moisture and light.
Stability: Stable under recommended storage conditions.