Kasivit Ashwagandha is a dietary supplement containing ashwagandha (Withania somnifera) root and black pepper (Piper nigrum) fruit in pullulan capsules. Ashwagandha is used in Ayurvedic medicine, the traditional healthcare system of India. In human trials, standardized ashwagandha root extracts lowered cortisol compared with placebo; results for stress and anxiety scores were mixed and the certainty of the evidence was rated low. Rare cases of liver injury have been reported, and effects on thyroid hormones have been described, so ask a doctor or pharmacist first if you take medicines or have a medical condition.*
Evidence Rating★★★★★Limited evidence · Trials tested standardized ashwagandha root extracts (certainty rated low); this product lists ashwagandha root, and no study of this product is cited
✓ Third-party tested · GMP-certified manufacturing facility (NSF International) · See testing standards ›
Ingredients: Ashwagandha (Withania somnifera)(root), Black Pepper (Piper nigrum)(fruit), pullulan capsules.
Science behind this product
The studies below tested standardized ashwagandha root extracts, often at 300 to 600 mg of extract a day. They did not test this product, which lists ashwagandha root, so their results may not apply to it. Most trials were short (weeks) and small.
Stress and anxiety
A meta-analysis of 12 randomized trials (1,002 participants) found lower anxiety and stress scores with ashwagandha extract than with placebo; the authors rated the certainty of the evidence as low, and results varied widely between trials. A separate meta-analysis of 7 trials of cortisol and 6 of perceived stress (488 participants) found lower cortisol but no significant effect on perceived stress scores.
Akhgarjand 2022 · Albalawi 2025
Sleep
A meta-analysis of 5 randomized trials (400 participants) found a small but significant improvement in overall sleep with ashwagandha extract compared with placebo, with larger effects in adults diagnosed with insomnia, at 600 mg a day or more and when treatment lasted 8 weeks or longer. The authors noted that data on serious adverse effects and long-term safety are limited.
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Fatigue and testosterone in men
In an 8-week crossover study of 57 overweight men aged 40-70 with mild fatigue, an ashwagandha extract was associated with a greater increase in DHEA-S and testosterone than placebo, but there were no significant differences between groups in fatigue, vigor or sexual well-being.
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Black pepper and medicines
Piperine, a main component of black pepper, inhibited the drug transporter P-glycoprotein and the enzyme CYP3A4 in laboratory experiments, and the authors concluded that dietary piperine could affect blood levels of medicines handled by these proteins. No study cited here tested whether black pepper changes the absorption of ashwagandha compounds. Ask a pharmacist before taking this product with prescribed medicines.
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Safety
A 2026 systematic review of 23 randomized trials (2,317 healthy adults) of standardized, root-only ashwagandha extracts at 125-600 mg a day for up to 180 days reported no serious adverse events attributable to the extract; mild stomach discomfort, headache and drowsiness were uncommon. The authors noted limited data beyond 180 days. Separately, case reports and case series describe liver injury (often with jaundice and itching) usually starting 2-12 weeks after beginning ashwagandha supplements, which in most cases resolved after stopping, although one liver transplant and three deaths in people with cirrhosis have been reported. Reviews also identify pregnant women, people with thyroid disorders and people with liver or kidney problems as higher-risk groups. Stop use and seek medical advice if you notice yellowing of the skin or eyes, itching, dark urine or nausea with tiredness.
Coope 2026 · Björnsson 2020 · McIntyre 2026 · Li 2026
Manufacturer Country: USA
Amount: 60 caps
Gross Weight: 0.25lb (113g)
Suggested Use: Take two (2) capsules once a day as a dietary supplement. For best results, take 20-30 min before a meal with an 8oz glass of water or as directed by your healthcare professional.
Caution: Do not exceed recommended dose. Pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.
Warning: This product is not intended to diagnose, treat, cure or prevent any disease. Keep out of reach of children. Do not use if the safety seal is damaged or missing. Store in a cool, dry place.
The Food and Drug Administration has not evaluated these statements. This product is not intended to diagnose, treat, cure or prevent any disease.
