General

Pronunciation:
os-pem-i-feen

Trade Name(s)

• Osphena

Ther. Class.

hormones

Pharm. Class.

estrogen agonists/antagonists

Indications

• Moderate to severe dyspareunia due to menopausal vulvar/vaginal atrophy.
• Moderate to severe vaginal dryness due to menopausal vulvar/vaginal atrophy.

Action

Has agonist (estrogen-like) effects on the endometrium of the uterus; effects are tissue-specific.

Therapeutic Effect(s):

• Decreased dyspareunia.
• Decreased vaginal dryness.

Pharmacokinetics

Absorption: Well absorbed following oral administration; food enhances absorption 2–3-fold.

Distribution: Extensively distributed to tissues.

Protein Binding: >99%.

Metabolism and Excretion: Mostly metabolized by the liver via the CYP3A4 and CYP2C9 isoenzymes; 75% excreted in feces, 7% in urine as metabolites; minimal amounts excreted unchanged in urine.

Half-life: 26 hr.

TIME/ACTION PROFILE (improvement in symptoms)

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity;
• Undiagnosed abnormal genital bleeding;
• History/suspicion of estrogen-dependent cancer;
• History of/current thromboembolic disorder, including deep vein thrombosis (DVT), pulmonary embolism (PE), MI, or stroke;
• Known or suspected breast cancer;
• Severe hepatic impairment;
• OB:  Pregnancy;
• Lactation: Lactation.

Use Cautiously in:

• Patients with risk factors for cardiovascular disease, arterial vascular disease, or venous thromboembolism (including hypertension, obesity, family history, tobacco use, diabetes mellitus, history of DVT/PE, or systemic lupus erythematosus);
• Long-term use (more than 4–5 yr); may ↑ risk of MI, stroke, invasive breast cancer, PE, DVT, and dementia in postmenopausal women;
• Women with a uterus (estrogen use without a progestin ↑ risk of endometrial cancer).

Adverse Reactions/Side Effects

CV: DVT, MI

Derm: ↑ sweating, hot flush

GU: genital/vaginal discharge

MS: muscle spasms

Neuro: STROKE

Resp: PE

Misc: HYPERSENSITIVITY REACTIONS (including angioedema), MALIGNANCY (BREAST, ENDOMETRIAL)

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

•  Fluconazole  may ↑ levels and risk of toxicity; avoid concurrent use.
•  CYP3A4 or CYP2C9 inhibitors, including  ketoconazole, may ↑ levels and risk of toxicity.
•  Rifampin  may ↓ levels and effectiveness; avoid concurrent use.
• Avoid concurrent use of other  estrogens  or  estrogen agonist/antagonists  due to ↑ estrogen effects.
• May displace or be displaced by other  drugs that are highly protein bound.

Route/Dosage

PO (Adults): 60 mg once daily.

Availability (generic available)

Tablets: 60 mg

Assessment

• Assess amount of pain during intercourse and vaginal dryness prior to and periodically during therapy. Determine methods previously used to treat dyspareunia.
• Assess BP before and periodically during therapy.
• Monitor for hypersensitivity reactions (angioedema, urticaria, rash, pruritus). If symptoms occur, discontinue ospemifene and provide supportive care.
• Inquire about breast health and date of last mammogram in postmenopausal women who have been on ospemifene long-term (4–5 yr).
• Assess periodically for signs or symptoms of PE such as dyspnea, chest pain, cough, tachycardia, DVT such as lower extremity edema, erythema, pain with movements or walking, and dementia (changes in baseline cognition or mental status) in postmenopausal women who have been on ospemifene long-term (4–5 yr). Discontinue use if PE or DVT suspected.

Implementation

• PO Administer once daily with food.

Patient/Family Teaching

• Explain purpose and side effects of ospemifene to patient. Instruct them to take medication as directed. Do not share medication with others, even if they have similar symptoms; may be harmful. Keep out of children's reach. Advise patient to read  Patient Information  sheet before starting therapy and with each Rx refill in case of changes.
• Advise patient to discuss dose and need for ospemifene every 3–6 mo as the shortest necessary duration of therapy is recommended.
• Advise women to follow yearly exams (pelvic exam, breast exam, mammogram) to monitor for breast and uterine cancer.
• Advise patient to report signs and symptoms of unusual vaginal bleeding, changes in vision or speech, sudden new severe headaches, severe pains in chest or legs with or without shortness of breath, weakness, or fatigue promptly to health care professional immediately.
• Inform patient that ospemifene may cause hot flashes, vaginal discharge, muscle spasm, and ↑ sweating.
• Patients who still have a uterus should discuss addition of progestin with health care professional.
• Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and consult health care professional before taking any new medications.
• Advise patient to notify health care professional of medication regimen before treatment or surgery.
• Caution patient that cigarette smoking, high BP, high cholesterol, diabetes, and being overweight during estrogen therapy may increase risk of heart disease.
• Rep:  May cause fetal harm. Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected and to avoid use during breastfeeding.

Evaluation/Desired Outcomes

• Decrease in pain during intercourse.
• Decreased vaginal dryness.