Ashwagandha Dosage: How Much to Take

Ashwagandha (Withania somnifera) is an adaptogenic herb used in Ayurvedic tradition and studied today as support for stress, sleep, and general resilience. The most common practical question is simply how much to take. Unlike many botanicals, ashwagandha has a reasonably consistent set of researched doses to anchor to. This guide summarises the amounts used in trials, how standardised extracts differ, and how to pick a product dosed like the ones in the studies. If you take medication or have a health condition, confirm your dose with the clinician who oversees your ashwagandha use first.

The doses used in research

Across the better stress and sleep trials, daily amounts clustered in a fairly narrow band:

Study	Extract	Daily dose	Outcome measured
Chandrasekhar 2012	Root extract	300 mg twice daily	Perceived stress, cortisol
Salve 2019	KSM-66	250-600 mg/day	Stress, sleep, cortisol
Langade 2019	Root extract	300 mg twice daily	Sleep quality

The pattern is clear: 300-600 mg per day of a concentrated root extract is the range most human evidence sits in. The 300 mg-twice-daily protocol from Chandrasekhar and colleagues is the single most-replicated schedule. The independent overview from NCCIH treats these amounts as the studied range while noting the evidence is still developing.

KSM-66 vs Sensoril and why standardisation matters

“Ashwagandha 500 mg” on a label tells you the powder weight, not the active content. Two branded extracts dominate research:

• KSM-66: a root-only extract, typically standardised to ≥5% withanolides, used across many stress and sleep RCTs, often at 300-600 mg/day.
• Sensoril: a root-and-leaf extract standardised to a higher withanolide percentage, usually dosed lower (around 125-250 mg/day) because it is more concentrated.

This is why you cannot compare two bottles on milligrams alone. A 250 mg Sensoril dose and a 600 mg KSM-66 dose can deliver similar withanolide loads. The Examine ashwagandha entry is a useful independent reference for how these extracts line up.

Evidence summary and timing

The evidence tier here is best described as moderate and emerging: several small-to-medium RCTs point in a consistent direction for stress and sleep, but long-term and large trials are still limited. Practically, that means ashwagandha is a slow-building support, not an on-demand calming agent. Most studies measured outcomes at six to eight weeks, so a fair trial is daily use across that window rather than a few days. For stress support, splitting the dose morning and evening is common; for sleep, a single evening dose is typical.

What to look for in an ashwagandha supplement for stress dosing

To match the researched amounts, useful selection criteria are:

• A named, standardised extract (KSM-66 or Sensoril) with the withanolide percentage stated, so you know the active load rather than just the powder weight.
• A per-serving dose in the studied range, roughly 300-600 mg/day for KSM-66-type extracts, lower for Sensoril-type.
• Third-party testing for identity and contaminants.
• A form and schedule you will actually keep up for six-plus weeks, since consistency drives the effect.

Our ashwagandha page details these criteria, and the stress guide shows where ashwagandha fits alongside other options. Ashwagandha supports the stress response; it does not treat an anxiety disorder or depression.

Cautions

Stay within the researched range, because more is not better and adds side-effect risk. Ashwagandha can cause drowsiness and digestive upset, has been linked to rare cases of liver injury, may lower blood sugar and blood pressure, and can affect thyroid hormone levels. It is generally avoided in pregnancy and by people on immunosuppressants or thyroid medication without medical guidance. Speak with your clinician before starting, especially if you take other medicines.

This article is educational and not medical advice. See our disclaimer and, if you are struggling, get help.