PROGESTERONE

(proe-jess'ter-one)

Crinone Gel, Endrometrin, Gesterol 50, Progestaject, Progestasert, Prometrium
Classifications: hormone; progestin;
Therapeutic: progestin
Pregnancy Category: X; vaginal gel in early pregnancy (category B)

Availability

100 mg capsules; 50 mg/mL injection; 8% gel; 100 mg vaginal insert

Action

Steroid hormone synthesized and released by testes, ovary, adrenal cortex, and placenta. Has estrogenic, anabolic, and androgenic activity. Physiologic precursor to estrogens, androgens, and adrenocortical steroids. Transforms endometrium from proliferative to secretory state; suppresses pituitary gonadotropin secretion, thereby blocking follicular maturation and ovulation. Acting with estrogen, promotes mammary gland development without causing lactation and increases body temperature 1° F at time of ovulation.

Therapeutic Effect

Relaxes estrogen-primed myometrium and prohibits spontaneous contraction of uterus. Sudden drop in blood levels of progestin (and estradiol) causes "withdrawal bleeding" from endometrium. Intrauterine placement of progesterone (intrauterine progesterone contraceptive system) hypothetically inhibits sperm survival, and suppresses endometrial proliferation (antiestrogenic effect).

Uses

Secondary amenorrhea, functional uterine bleeding, endometriosis, and premenstrual syndrome. As an intrauterine agent (Progestasert) and in combination with estrogens provides fertility control. Largely supplanted by new progestins, which have longer action and oral effectiveness. Treatment of infertile women with progesterone deficiency.

Contraindications

Hypersensitivity to progestins, known or suspected breast or genital malignancy; use as a pregnancy test; thrombophlebitis, thromboembolic disorders; ectopic pregnancy; cerebral apoplexy (or its history); severely impaired liver function or disease; undiagnosed vaginal bleeding, incomplete abortion; use during first 4 mo of pregnancy (category X), other than vaginal gel used for assisted reproductive technology (ART) in early pregnancy. Progestasert: Pregnancy or suspicion of pregnancy. Prometrium (oral): Patients with peanut allergy.

Cautious Use

Anemia; diabetes mellitus; history of psychic depression; persons susceptible to acute intermittent porphyria or with conditions that may be aggravated by fluid retention (asthma, seizure disorders, cardiac or kidney function, migraine); impaired liver function; previous ectopic pregnancy; presence or history of salpingitis; venereal disease; unresolved abnormal Pap smear; genital bleeding of unknown etiology; previous pelvic surgery.

Route & Dosage

Amenorrhea
Adult: IM 5–10 mg for 6–8 consecutive days PO 400 mg h.s. x 10 d Vaginal gel 45 mg every other day (up to 6 doses)

Uterine Bleeding
Adult: IM 5–10 mg/d for 6 d

Premenstrual Syndrome
Adult: PR 200–400 mg/d

Intrauterine Contraceptive
Adult: Intrauterine Insert in uterus for 1 y

Assisted Reproductive Technology
Adult: Vaginally 90 mg gel q.d. or b.i.d. until placental autonomy OR 10–12 wk; 100 mg insert 2–3 times daily up to 10 wk

Administration

Intramuscular

Immerse vial in warm water momentarily to redissolve crystals (if present) and to facilitate aspiration of drug into syringe.
Inject deeply IM. Injection site may be irritated. Inspect IM sites carefully and rotate areas systematically.
Do not give oral capsules, which contain peanut oil, to patients allergic to peanuts.
Store drug at 15°–30° C (59°–86° F) unless otherwise specified by manufacturer. Protect from freezing and light.

Adverse Effects (≥1%)

CNS: Migraine headache, dizziness, lethargy, mental depression, somnolence, insomnia. CV: Thromboembolic disorder, pulmonary embolism. Special Senses: Change in vision, proptosis, diplopia, papilledema, retinal vascular lesions. GI: Hepatic disease, cholestatic jaundice; nausea, vomiting, abdominal cramps. Urogenital: Vaginal candidiasis, chloasma, cervical erosion and changes in secretions, breakthrough bleeding, dysmenorrhea, amenorrhea, pruritus vulvae. Metabolic: Hyperglycemia, decreased libido, transient increase in sodium and chloride excretion, pyrexia. Skin: Acne, pruritus, allergic rash, photosensitivity, urticaria, hirsutism, alopecia. Body as a Whole: Edema, weight changes; pain at injection site; fatigue. Endocrine: Gynecomastia, galactorrhea.

Diagnostic Test Interference

progestins may decrease levels of urinary pregnanediol and increase levels of serum alkaline phosphatase, plasma amino acids, urinary nitrogen, and coagulation factors VII, VIII, IX, and X. They also decrease glucose tolerance (may cause false-positive urine glucose tests) and lower HDL (high-density lipoprotein) levels.

Interactions

Drug: barbiturates, carbamazepine, phenytoin, rifampin may alter contraceptive effectiveness; ketoconazole may inhibit progesterone metabolism; may antagonize effects of bromocriptine.

Pharmacokinetics

Absorption: Rapid from IM site; PO peaks at 3 h. Metabolism: Extensively in liver. Elimination: Primarily in urine; excreted in breast milk. Half-Life: 5 min.

Nursing Implications

Assessment & Drug Effects

Record baseline data for comparative value about patient's weight, BP, and pulse at onset of progestin therapy. Report deviations promptly.
Lab tests: Periodic liver function tests, blood glucose, and serum electrolytes.
Monitor for and report immediately S&S of thrombophlebitis or thromboembolic disease.
Be alert for S&S of acute intermittent porphyria in susceptible patients (e.g., severe, colicky abdominal pain, vomiting, distention, diarrhea, constipation).

Patient & Family Education

Avoid exposure to UV light and prolonged periods of time in the sun. Photosensitivity severity is related to both time of exposure and dose. A phototoxic drug reaction usually looks like an exaggerated sunburn and occurs within 5–18 h after exposure to sun and is maximal by 36–72 h.
Use sunscreen lotion (SPF >12) that contains paraaminobenzoic acid (PABA) on exposed skin surfaces whenever outdoors, even on dark days.
Inform physician promptly if any of the following occur: Sudden severe headache or vomiting, dizziness or fainting, numbness in an arm or leg, pain in calves accompanied by swelling, warmth, and redness; acute chest pain or dyspnea.
Report to physician promptly unexplained sudden or gradual, partial or complete loss of vision, ptosis, or diplopia.
Monitor for loss of glycemic control if diabetic.
Notify physician if you become or suspect pregnancy. Learn the potential risk to the fetus from exposure to progestin.

Intrauterine Progesterone Contraceptive System (Progestasert)

Use another method of birth control (foam or condom) during the first 2 mo of Progestasert use.
Regular cyclic pattern of ovulation continues while Progestasert is in place.
Be prepared for heavier and longer menstrual periods during Progestasert use. Consult physician if increased menstrual bleeding continues.
Check Progestasert threads frequently during first few months and after menstruation (times when expulsion is most likely to occur). If you cannot feel threads, return to physician for an examination and prescription for another method of birth control.
Do not pull on threads for any reason. If the IUD is partially expelled, it should be removed; however, do not try to remove it yourself nor allow your partner to attempt to do so.
Consult physician if a period is missed and pregnancy is suspected. Remove the device during pregnancy.
Report to the physician for immediate treatment if you experience fever, acute pelvic pain and tenderness, unusual bleeding, or severe cramping. These are symptoms that indicate infection.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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