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Limited evidenceBrain & cognition

Pregnenolone

Pregnenolone is the upstream neurosteroid precursor, marketed for memory and mood on essentially no data in healthy people. The modest positive trials are in psychiatric populations at 400-500 mg/day, and they are small, inconsistent and unreplicated.

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What the science says

  • No evidence for memory or cognition in healthy adults Limited evidence

    There are no controlled trials showing pregnenolone improves memory, focus or cognition in healthy people. The memory claims trace back to 1940s-era industrial studies and rodent work, not modern clinical research.

  • Schizophrenia adjunct: mixed at best Limited evidence

    In the largest RCT (120 participants randomized, 8 weeks of adjunctive pregnenolone), the primary cognitive endpoint - the MATRICS composite - was not improved. A secondary measure of functional capacity (UPSA-B) did improve (p = 0.03), and negative symptoms did not change because baseline scores were already very low. Other small add-on trials report negative-symptom benefits while several are null.

  • Bipolar depression: one promising but unreplicated RCT Limited evidence

    Eighty adults with bipolar depression were randomized to pregnenolone titrated to 500 mg/day or placebo for 12 weeks as add-on therapy. There was a significant treatment-by-week interaction on the Hamilton Depression scale (p = 0.025) and higher remission by self-report (61% vs 37%), but the effect did not appear consistently across all scales and has not been replicated.

Dosage & safety

Studied doseTrials use 100-500 mg/day, with the bipolar depression study titrating to 500 mg/day for 12 weeks. Consumer supplements typically contain 10-50 mg - doses with no efficacy data whatsoever.
SafetyPregnenolone is converted into progesterone, DHEA, androgens and estrogens, so it can produce hormone-related effects: acne, irritability, headache, insomnia and menstrual changes. Short-term trials up to 500 mg/day report good tolerability, but long-term safety is unknown and effects on the endometrium and prostate are unstudied. Avoid with hormone-sensitive cancers and in pregnancy or breastfeeding. Its status under anti-doping rules is ambiguous - related prohormones including DHEA are banned outright - so tested athletes should avoid it. Prescription-only or unapproved as a supplement in many countries outside the US.

How to take it

TimingMorning — insomnia and irritability are common complaints with evening doses.
With food?With a meal containing fat; it is a fat-soluble steroid.
Worth knowingThe 10–50 mg in consumer capsules and the 100–500 mg used in trials are different products in practice — a label dose has never been tested for anything.

Interactions

With medications

  • oestrogen, progesterone or testosterone therapy

    pregnenolone is converted into these same hormones, adding an unmeasured amount to a prescribed dose do not combine without your prescriber's involvement

With other supplements

  • DHEA and other prohormones

    both feed the same steroid pathway, compounding androgenic and oestrogenic effects do not stack them

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does pregnenolone improve memory?

There are no controlled trials showing pregnenolone improves memory, focus or cognition in healthy people. The memory claims trace back to 1940s-era industrial studies and rodent work, not modern clinical research.

Does pregnenolone help depression?

The evidence for pregnenolone in depression is limited to one unreplicated trial of eighty adults with bipolar depression, where add-on pregnenolone titrated to 500 mg/day for 12 weeks showed some benefit that was not consistent across all scales. There is no evidence for it in healthy people.

How much pregnenolone should I take?

No effective pregnenolone dose is established for healthy people. Trials used 100-500 mg/day in psychiatric patients, while consumer supplements typically contain 10-50 mg, a dose with no efficacy data at all.

What are the side effects of pregnenolone?

Pregnenolone is converted into progesterone, DHEA, androgens and estrogens, so it can cause acne, irritability, headache, insomnia and menstrual changes. Long-term safety is unknown; avoid it with hormone-sensitive cancers, in pregnancy, and if you are a tested athlete.

Scientific references

Where to buy

Double Wood Supplements, Pregnenolone, 120 Capsules (50 mg per Capsule)

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