What is the appropriate dosage and usage of medroxyprogesterone (MPA) for an adult female patient?

Medroxyprogesterone Acetate (MPA) Dosing and Usage

For adult females, medroxyprogesterone acetate dosing varies dramatically by indication: 5-10 mg daily for 5-14 days for menstrual disorders, 400-600 mg daily for fertility-preserving treatment of endometrial cancer, 150 mg intramuscularly every 3 months for contraception, or 10 mg twice daily for osteoporosis prevention. 1

Gynecologic Indications

Secondary Amenorrhea

• Administer 5-10 mg daily for 5-10 days, with 10 mg for 10 days being optimal for adequate secretory transformation 1
• Therapy may be started at any time 1
• Progestin withdrawal bleeding typically occurs within 3-7 days after discontinuation 1

Abnormal Uterine Bleeding

• Give 5-10 mg daily for 5-10 days, beginning on day 16 or 21 of the menstrual cycle 1
• For optimal secretory transformation, use 10 mg daily for 10 days starting on cycle day 16 1
• Withdrawal bleeding occurs within 3-7 days after stopping therapy 1
• Patients with recurrent episodes benefit from planned menstrual cycling 1

Endometrial Protection in Hormone Replacement Therapy

• Prescribe 5-10 mg daily for 12-14 consecutive days per month in postmenopausal women receiving 0.625 mg conjugated estrogens 1
• Begin either on cycle day 1 or day 16 1
• Start at the lowest effective dose and re-evaluate every 3-6 months 1
• Perform endometrial sampling when indicated for undiagnosed persistent or recurrent vaginal bleeding 1

Oncologic Indications

Fertility-Preserving Treatment for Endometrial Cancer

• Use 400-600 mg daily as the recommended dose for conservative management 2
• Alternative: megestrol acetate 160-320 mg daily 2
• Assess response at 6 months with dilation and curettage plus imaging 2
• Response rates reach approximately 75%, but recurrence rates are 30-40% 2
• After complete response, encourage immediate conception with referral to fertility clinic 2
• Perform hysterectomy with salpingo-oophorectomy after childbearing completion 2

Appetite Stimulation in Cancer Cachexia

• The minimum effective dose is 200 mg daily, though optimal dosing remains undefined 2
• MPA significantly increases appetite (level of evidence B1) but weight gain effects are unconfirmed (level of evidence C) 2
• Use only after failure of dietetic and oral nutritional management 2

Contraceptive Use

Depot Medroxyprogesterone Acetate (DMPA)

• Administer 150 mg intramuscularly every 3 months (12-13 weeks) 3
• Serum concentrations plateau at approximately 1.0 ng/mL for about 3 months 3
• MPA may be detectable for up to 9 months after a single injection 3
• Schedule follow-up visits every 11-12 weeks for adolescents to accommodate missed appointments 4

Other Indications

Endometriosis Treatment

• Use 50 mg daily orally for 4 months 5
• This regimen improved symptoms and disease staging in 80% of patients 5
• Induces amenorrhea in 75% of patients, with breakthrough bleeding in 20% 5
• Suppresses ovulation and reduces LH and estradiol levels 5

Osteoporosis Prevention

• Administer 10 mg twice daily (20 mg total daily dose) 6
• Efficacious in preventing postmenopausal bone loss 6
• Particularly useful in women with contraindications to estrogen therapy 6

Critical Safety Considerations

Thromboembolic Risk

• Thromboembolism is the most serious adverse effect, occurring in approximately 1 in 6 patients, with mortality risk of 1 in 23 patients 4
• Monitor all patients carefully for signs of deep venous thrombosis or pulmonary embolism 4
• This risk is significantly elevated compared to other progestins 4

Weight Gain Management

• Weight gain at 6 months strongly predicts excessive future weight gain with continued use 4
• Monitor weight regularly, especially during the first 6 months 4
• Weight gain represents adipose tissue accumulation rather than lean muscle mass 4
• Consider alternative contraceptive methods if significant weight gain occurs within 6 months 4

Menstrual Changes

• Irregular vaginal bleeding is extremely common, including breakthrough bleeding and amenorrhea 4
• Provide thorough pre-treatment counseling about expected menstrual changes to improve continuation rates 4
• Amenorrhea occurs in 75% of patients on 50 mg daily for endometriosis 5

Contraindications

• Avoid in patients with hormone receptor-positive cancers 7
• Micronized progesterone (not MPA) is contraindicated with severe peanut allergies due to peanut oil excipients 7

Administration Considerations

Route Selection

• Oral MPA is absorbed and effective for most gynecologic indications 1, 5
• Intramuscular depot formulation provides sustained release over 3 months for contraception 3
• Self-administration of subcutaneous DMPA shows equivalent efficacy and safety to provider administration 4

Monitoring Requirements

• Re-evaluate patients on HRT every 3-6 months to determine continued necessity 1
• Perform endometrial sampling for undiagnosed persistent or recurrent vaginal bleeding 1
• Monitor for thromboembolic events throughout treatment 4
• Assess weight regularly, particularly in first 6 months of DMPA use 4

Common Pitfalls to Avoid

• Failing to counsel patients about expected menstrual changes before initiating therapy significantly reduces continuation rates 4
• Not monitoring weight during the first 6 months of DMPA use misses the critical window for predicting excessive weight gain 4
• Overlooking thromboembolic risk assessment, which carries significant morbidity and mortality 4
• Using doses above 480 mg daily for appetite stimulation provides no additional benefit 2
• Failing to supplement calcium and vitamin D when using MPA for bone health 4