Ashwagandha may enhance SSRI effects
Ashwagandha has mild serotonergic and GABAergic activity. Adding it to an SSRI is not known to cause serotonin syndrome but may potentiate sedation, dizziness, or mood changes, especially during dose changes.
If on an SSRI, introduce ashwagandha at a low dose (300mg) and monitor. Discuss with your prescriber before adding.
If combined, take at different times of day to separate peak effects
Ashwagandha may enhance SSRI effects. If on an SSRI, introduce ashwagandha at a low dose (300mg) and monitor. Discuss with your prescriber before adding.
If combined, take at different times of day to separate peak effects
This interaction is rated “Caution” by Formulate. Ashwagandha has mild serotonergic and GABAergic activity. Adding it to an SSRI is not known to cause serotonin syndrome but may potentiate sedation, dizziness, or mood changes, especially during dose changes.
Studies from our registry that mention ashwagandha or ssri. Each links to the primary source and the other Formulate pages citing it.
Mentions ashwagandha · 2026
Memorial Sloan Kettering Integrative Medicine Monograph: Ashwagandha
Primary literature · Monograph
Documents thyrotoxicosis case reports associated with ashwagandha use. States ashwagandha may increase thyroxine levels. Also notes CYP3A4 induction (moderate) and sedative-additive effects. Does not give a hard avoid-with-levothyroxine warning but flags thyroid monitoring.
Mentions ssri · 2024
St. John's Wort — StatPearls
Primary literature · Monograph
Identifies SSRIs (sertraline, paroxetine, fluoxetine, citalopram) as high-concern co-administration targets due to serotonin syndrome risk. Typical SJW doses implicated: 600-900 mg/day standardized extract. Typical SSRI doses in case reports: 20-75 mg/day.
Mentions ashwagandha · 2022
Ashwagandha as a Unique Cause of Thyrotoxicosis Presenting with Supraventricular Tachycardia
Primary literature · Case report
Patient presented with supraventricular tachycardia and biochemical thyrotoxicosis after two years of self-administered ashwagandha. Full symptomatic and biochemical resolution after cessation, with no other intervention.
Mentions ashwagandha · 2019
An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract
Lopresti et al. · Medicine
240mg/day high-concentration extract produced significant cortisol and stress-score reductions at 60 days.
Mentions ashwagandha · 2019
An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract
Salve J, Pate S, Debnath K, Langade D · Cureus
8-week RCT (n=60) showed ashwagandha 250mg and 600mg daily significantly reduced perceived stress, serum cortisol, and improved sleep quality vs placebo, with greater effect at the higher dose.
Mentions ashwagandha · 2018
Efficacy and Safety of Ashwagandha Root Extract in Subclinical Hypothyroid Patients: A Double-Blind, Randomized Placebo-Controlled Trial
Sharma et al. · J Altern Complement Med
TSH decreased significantly (p<0.001); T3 increased significantly (p=0.0031); T4 increased significantly (p=0.0096). Direction of effect consistent with thyroid-stimulating action of ashwagandha.
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Other interactions to know
Combining St John's wort with any SSRI risks serotonin syndrome — a potentially fatal hyperserotonergic state.
Risk of serotonin syndrome
SAM-e with SSRIs: Serotonin syndrome risk
Ashwagandha can raise thyroid hormone levels and stack additively with levothyroxine, risking thyrotoxicosis.
May enhance sedative effects
Melatonin may enhance SSRI side effects
Rhodiola may have mild MAOI effects
Piperine may enhance ashwagandha absorption
Check your full stack in the free interaction checker.
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Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.
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