Ray Peat on Cyproheptadine

January 3, 2026

Factors for healthier pregnancies and the postpartum period

"The most important factors that can be optimized with existing resources. Healthier pregnancies lead to a healthier and happier life after birth. These factors include sunlight, vitamin D, milk, cheese, eggs, fruit and well-cooked vegetables, high-fiber foods, and optimizing thyroid function and pregnenolone and progesterone (which support mitochondrial function and protect against aldosterone, parathyroid hormone, excess serotonin, CRK and cortisol, as well as increasing allopregnanolone), and using the safest anti-inflammatory and antiserotonergic medications such as aspirin and cyproheptadine when needed."

May 2019 – Ray Peat's Newsletter

Mitigation of the harmful effects of excess serotonin

"Avoiding prolonged fasting and stressful physical activity, which increase free fatty acids; combining sugars with proteins to keep free fatty acids low; using aspirin, niacinamide, or cyproheptadine to reduce the formation of free fatty acids during unavoidable stress; avoiding an excess of phosphate relative to calcium in the diet; consuming milk and other anti-stress foods before bed or during the night; and staying in a brightly lit environment during the day with regular sunlight exposure can minimize the harmful effects of excess serotonin and reduce the associated inflammation, fibrosis, and atrophy."

July 2019 – Ray Peat's Newsletter

Versatile benefits of cyproheptadine for sleep and cancer

"Cyproheptadine, 2 to 4 mg before bedtime, would help with both sleep and cancer. It also blocks calcium, antagonizes aldosterone, and reverses the antidiuretic effect of serotonin."

Email Response by Ray Peat

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