Phytoestrogens (isoflavones, daidzein, genistein, ipriflavone, ostivone, soy isoflavones)

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