Medroxyprogesterone Acetate

medroxyprogesterone acetate (me drox' ee proe jess' te rone) Oral:

Alti-MPA (CAN), Amen, Curretab, Cycrin, Gen-Medroxy (CAN), NovoMedrone (CAN), Provera Parenteral, antineoplastic:

Depo-Provera Pregnancy Category X Drug classes

Hormone Progestin Antineoplastic Therapeutic actions

Progesterone derivative; endogenous progesterone transforms proliferative endometrium into secretory endometrium; inhibits the secretion of pituitary gonadotropins, which prevents follicular maturation and ovulation; inhibits spontaneous uterine contraction. Indications

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Reduction of endometrial hyperplasia in postmenopausal women Oral: Treatment of secondary amenorrhea Oral: Abnormal uterine bleeding due to hormonal imbalance in the absence of organic pathology Parenteral: Adjunctive therapy and palliation of inoperable, recurrent, and metastatic endometrial carcinoma or renal carcinoma Unlabeled use for depot form: Long-acting contraceptive, treatment of breast cancer

Contraindications and cautions

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Contraindicated with allergy to progestins; thrombophlebitis, thromboembolic disorders, cerebral hemorrhage or history of these conditions; hepatic disease, carcinoma of the breast, ovaries, or endometrium, undiagnosed vaginal bleeding, missed abortion; pregnancy (fetal abnormalities, including masculinization of the female fetus have been reported); lactation. Use cautiously with epilepsy, migraine, asthma, cardiac or renal dysfunction.

Available forms

Tablets—2.5, 5, 10 mg; with estradiol—25 mg medroxyprogesterone and 5 mg estradiol cypionate per 0.5 mL; injection—150, 400 mg/mL Dosages ADULTS

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Contraception monotherapy: 150 mg IM q 3 mo.

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Secondary amenorrhea: 5–10 mg/day PO for 5–10 days. A dose for inducing an optimum secretory transformation of an endometrium that has been primed with exogenous or endogenous estrogen is 10 mg/day for 10 days. Start therapy at any time; withdrawal bleeding usually occurs 3–7 days after therapy ends. Abnormal uterine bleeding: 5–10 mg/day PO for 5–10 days, beginning on the 16th or 21st day of the menstrual cycle. To produce an optimum secretory transformation of an endometrium that has been primed with estrogen, give 10 mg/day PO for 10 days, beginning on the 16th day of the cycle. Withdrawal bleeding usually occurs 3–7 days after discontinuing therapy. If bleeding is controlled, administer two subsequent cycles. Endometrial or renal carcinoma: 400–1,000 mg/wk IM. If improvement occurs within a few weeks or months and the disease appears stabilized, it may be possible to maintain improvement with as little as 400 mg/mo IM. Reduction of endometrial hyperplasia: 5–10 mg/day PO for 12–14 days/mo.

Pharmacokinetics Route Oral IM

Onset Slow Weeks

Peak Unknown Months

Metabolism: Hepatic; T1/2: Unknown Distribution: Crosses placenta; enters breast milk Excretion: Unknown Adverse effects

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CNS: Sudden, partial, or complete loss of vision; proptosis, diplopia, migraine, precipitation of acute intermittent porphyria, mental depression, pyrexia, insomnia, somnolence, nervousness, fatigue CV: Thrombophlebitis, cerebrovascular disorders, retinal thrombosis, pulmonary embolism, thromboembolic and thrombotic disease, increased BP Dermatologic: Rash with or without pruritus, acne, melasma or chloasma, alopecia, hirsutism, photosensitivity, pruritus, urticaria GI: Cholestatic jaundice, nausea GU: Breakthrough bleeding, spotting, change in menstrual flow, amenorrhea, changes in cervical erosion and cervical secretions, breast tenderness and secretion Other: Fluid retention, edema, increase or decrease in weight, decreased glucose tolerance

Interactions

Drug-lab test • Inaccurate tests of hepatic and endocrine function Nursing considerations Assessment

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History: Allergy to progestins; thrombophlebitis; thromboembolic disorders; cerebral hemorrhage; hepatic disease; carcinoma of the breast, ovaries, or endometrium; undiagnosed vaginal bleeding; missed abortion; epilepsy; migraine; asthma; cardiac or renal dysfunction; pregnancy; lactation Physical: Skin color, lesions, turgor; hair; breasts; pelvic exam; orientation, affect; ophthalmologic exam; P, auscultation, peripheral perfusion, edema; R, adventitious sounds; liver evaluation; liver and renal function tests, glucose tolerance, Pap smear

Interventions

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Arrange for pretreatment and periodic (at least annual) history and physical, which should include BP, breasts, abdomen, pelvic organs, and a Pap smear. Before therapy begins, caution patient to prevent pregnancy and to have frequent medical follow-up visits. Discontinue medication and consult physician if sudden, partial, or complete loss of vision occurs; if papilledema or retinal vascular lesions are present, discontinue drug. Discontinue medication and consult physician at the first sign of thromboembolic disease (leg pain, swelling, peripheral perfusion changes, shortness of breath).

Teaching points

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If you are taking the oral form of this drug, mark days you should take the medication on a calendar. This drug should not be taken during pregnancy due to risk of serious fetal abnormalities; using barrier contraceptives is suggested. These side effects may occur: Sensitivity to light (avoid exposure to the sun; use sunscreen and protective clothing); dizziness, sleeplessness, depression (use caution driving or performing tasks that require alertness); skin rash, color changes, loss of hair; fever; nausea. Report pain or swelling and warmth in the calves, acute chest pain or shortness of breath, sudden severe headache or vomiting, dizziness or fainting, visual disturbances, numbness or tingling in the arm or leg.

Adverse effects in Italic are most common; those in Bold are life-threatening.