Phytoestrogens (isoflavones, daidzein, genistein, ipriflavone, ostivone, soy isoflavones)
Classes: Urology, Herbals
Suggested dosing of Isoflavones, daidzein (phytoestrogens)
Isoflavones
40 mg PO qd
Menopausal symptoms: 34-120 mg/d
Hypertension: 18 mg PO BId
Lung cancer prevention: 8.3 -83.2 mcg/d
Ipriflavone
200 mg PO TId
CrCl 40-80 mL/min
200 mg PO BId
CrCl <40 mL/min
200 mg PO qd
Suggested uses of Isoflavones, daidzein (phytoestrogens)
Menopausal vasomotor symptoms, osteoporosis
Decrease risk of breast cancer, CVd
Efficacy
Studies show reasonable efficacy for breast cancer, diabetes, osteoporosis prevention/treatment, hot flashes, CVD risk
Mixed results for cancer prevention
Isoflavones, daidzein (phytoestrogens) adverse (side) effects
Frequency not defined
Allergic reaction
Warnings
Contraindications
Pregnancy
Pregnancy and lactation
Pregnancy category: avoid use
Lactation: N/A
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Isoflavones, daidzein (phytoestrogens)
Metabolism: N/A
Excretion: N/A
Mechanism of action
Partial estrogen receptor agonists; anti-estrogenic effects in premenopausal women, but weak estrogenic effects in postmenopausal women
May stimulate osteoblastic activity
Incr sex hormone binding globulin (SHBG) levels; antioxidant activity