Elagolix Dosage and Management for Endometriosis
For endometriosis-associated pain, elagolix is recommended at 150 mg once daily for up to 24 months or 200 mg twice daily for up to 6 months, with dose selection based on pain severity and consideration of bone mineral density effects. 1
Dosing Recommendations
Standard dosing options:
- 150 mg once daily (for up to 24 months)
- 200 mg twice daily (for up to 6 months)
Adjusted dosing for special populations:
- Moderate hepatic impairment: 150 mg once daily for up to 6 months
- Severe hepatic impairment: Contraindicated
- Patients taking OATP1B1 inhibitors: Not recommended due to significant increase in elagolix plasma concentrations
Efficacy Profile
Elagolix demonstrates significant efficacy for endometriosis-associated pain:
Higher-dose regimen (200 mg twice daily) provides more substantial pain relief:
- 72-76% response rate for dysmenorrhea
- 55-58% response rate for nonmenstrual pelvic pain 2
Lower-dose regimen (150 mg once daily) provides moderate relief:
- 43-46% response rate for dysmenorrhea
- 50% response rate for nonmenstrual pelvic pain 2
Pain reduction is maintained throughout the treatment period, with 12-month data showing sustained efficacy 3
Monitoring Recommendations
Bone mineral density (BMD):
- Baseline BMD assessment recommended before initiating therapy
- Consider periodic monitoring, especially with higher dose or longer duration
- BMD decreases are dose-dependent and may not be completely reversible 1
Liver function:
- Monitor for signs of liver injury (jaundice, dark urine, fatigue, right upper quadrant pain)
- Dose-dependent elevations in ALT may occur 1
Pregnancy testing:
- Perform before initiating treatment
- Periodic testing during treatment due to altered menstrual bleeding patterns
- Discontinue immediately if pregnancy is confirmed 1
Mental health:
- Monitor for depression, anxiety, mood changes, and suicidal ideation
- Advise patients to report new or worsening mood symptoms 1
Treatment Duration Considerations
Duration limits based on dose:
- 150 mg once daily: up to 24 months
- 200 mg twice daily: up to 6 months
- Moderate hepatic impairment: up to 6 months (150 mg once daily only)
Treatment response evaluation:
- Assess efficacy after 3 months of therapy
- Consider dose adjustment if inadequate response with lower dose
Contraindications
Elagolix is contraindicated in:
- Pregnancy
- Known osteoporosis
- Severe hepatic impairment
- Concurrent use of strong OATP1B1 inhibitors
- Hypersensitivity to elagolix 1
Common Side Effects
- Hot flashes and night sweats (most common)
- Headache
- Nausea
- Insomnia
- Amenorrhea
- Anxiety
- Arthralgia
- Depression and mood changes 1
Contraception Considerations
- Use non-hormonal contraception during treatment and for 28 days after discontinuation
- Coadministration with estrogen-containing contraceptives is not recommended with 200 mg twice daily dose
- May reduce efficacy of progestin-containing oral contraceptives 1
Place in Therapy
While combined oral contraceptives and progestins are recommended as first-line treatments for endometriosis 4, elagolix offers an important option for patients who:
- Have inadequate response to first-line therapies
- Cannot tolerate or have contraindications to first-line options
- Have moderate to severe endometriosis-associated pain requiring more potent hormonal suppression
Clinical Pearls
- Missed doses should be taken as soon as remembered on the same day, without doubling up
- Higher dose (200 mg twice daily) provides greater pain relief but has more hypoestrogenic side effects and shorter allowable treatment duration
- Consider bone health status before initiating therapy, particularly in patients with risk factors for osteoporosis
- Elagolix offers the advantage of rapid reversibility compared to GnRH agonists, with quick return of menses after discontinuation