Progesterone's best-supported role is protecting the womb lining in women also taking estrogen. It may ease hot flashes and night sweats and improve sleep through a calming brain chemical. Support for bone, brain, heart, and longevity is weak. Main trade-offs are next-morning grogginess, breast tenderness, spotting, and a small breast-cancer risk with long-term combined use. (Full Review)

Protocol

Dose

100 mg continuous / 200 mg cyclic

Oral micronized progesterone alongside estrogen

Timing

At bedtime

Aligns sedation with sleep

Frequency

Once daily

Short half-life; single evening dose

Time to effect

Endometrial Protection

Continuous

While dosing is maintained

Hot Flash Relief

Several weeks

Builds gradually

Sleep & Calming

First night

Same-day effect

Benefits

High: Endometrial protection during estrogen therapy

Medium: Relief of hot flashes and night sweats; improved sleep

Low: Bone formation support; favorable cardiovascular and metabolic profile versus synthetic progestins; neuroprotection and brain-injury recovery

Speculative: Longevity and healthspan extension; calmer mood and stress resilience

Contraindications

Breast or other hormone-sensitive cancer

Venous thromboembolism, prior clots, or clotting disorder

Active liver disease (Child-Pugh Class B–C) or acute liver dysfunction

Undiagnosed vaginal bleeding

Peanut allergy with peanut-oil-based capsules

Key Interactions

Strong CYP3A4 inducers (rifampin, carbamazepine, phenytoin, phenobarbital, St. John's Wort)

Strong CYP3A4 inhibitors (ketoconazole, ritonavir, clarithromycin)

Sedating antihistamines (diphenhydramine, doxylamine)

Sedating supplements (melatonin, valerian, kava, cannabidiol)

Additive sedatives: alcohol, benzodiazepines (diazepam, lorazepam), opioids, Z-drugs (zolpidem)

Grapefruit juice

Oral estrogen as partner (clot risk)

Risk & Side Effects

High: Drowsiness and next-day sedation

Medium: Breast tenderness and fluid retention; irregular bleeding and spotting; mood changes and headache

Low: Breast cancer risk with long-term combined use; venous blood clots

Speculative: Depression with long-term use; unknown effects of decades-long use

Monitoring

Marker	Target	Why
Estradiol (serum)	~50–150 pg/mL on therapy	Confirms the estrogen level progesterone is balancing
Progesterone (serum)	>3–5 ng/mL after vaginal dosing; not a reliable target for oral capsules	May confirm vaginal delivery; limited use for oral route
Follicle-stimulating hormone, FSH (serum)	Elevated (often >25 IU/L) confirms menopause	Establishes menopausal status at baseline
Endometrial thickness (ultrasound)	<4–5 mm in postmenopausal women	Detects estrogen overstimulation of the uterine lining
Lipid panel	LDL-C <100 mg/dL; HDL-C >50 mg/dL	Confirms progesterone's neutral metabolic effect and tracks background cardiovascular risk

Cadence: Initial review at 6–12 weeks, then reassessment every 6–12 months; evaluate any abnormal bleeding promptly

Qualitative Assessment

Sleep quality — falling asleep more easily and fewer night-time awakenings
Hot flashes and night sweats — reduced frequency and intensity
Mood and anxiety — steadier mood and calmer stress response
Bleeding pattern — predictable withdrawal bleed on sequential dosing, or settling of spotting on continuous dosing
Daytime alertness — absence of next-morning grogginess

Progesterone for Health & Longevity

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment