What is the recommended dose and potential side effects of Ashwagandha (Withania somnifera)?

Ashwagandha Dosing and Side Effects

The recommended dose of Ashwagandha (Withania somnifera) root extract is 300-500 mg twice daily, with clinical studies showing efficacy and safety at this dosage range for stress reduction, anxiety, and improved well-being. 1, 2, 3

Recommended Dosing

• Standard dosing:

  • 300-500 mg of standardized root extract twice daily 1, 2
  • Most clinical studies use extracts standardized to contain 2.5-5% withanolides
  • Duration of treatment in clinical trials typically ranges from 8-12 weeks

• Specific formulations studied:

  • 300 mg high-concentration full-spectrum extract twice daily (total 600 mg/day) 1
  • 500 mg standardized extract (2.5% withanolides) with 5 mg piperine once daily 2
  • 600 mg/day for elderly populations 4

Potential Benefits

Ashwagandha has demonstrated several benefits in clinical studies:

1. Stress and anxiety reduction:

   • Significant reduction in stress assessment scores (p<0.0001) 1
   • Reduced serum cortisol levels (p=0.0006) 1
   • Improvement in Hamilton Anxiety Rating Scale scores 2

2. Mood improvement:

   • Alleviates symptoms of mild to moderate depression 2
   • Increases serum serotonin levels 2

3. Sleep quality:

   • Improves sleep quality in both general and elderly populations 2, 4
   • Enhances mental alertness upon waking 4

4. Physical performance:

   • May increase velocity, power, and VO₂ max in healthy young adults 5
   • Potentially beneficial for general weakness and muscular strength 5

Side Effects and Safety Profile

Ashwagandha is generally well-tolerated at recommended doses, with mild adverse effects reported:

• Common side effects:

  • Mild gastrointestinal disturbances (comparable to placebo in most studies) 1, 3
  • Headache
  • Drowsiness

• Safety considerations:

  • No significant changes in hematological parameters, liver function, or thyroid function in 8-week safety studies 3
  • No serious adverse events reported in clinical trials 1, 3
  • Well-tolerated by elderly populations 4

Precautions and Contraindications

• Pregnancy and breastfeeding: Limited safety data; traditionally avoided
• Autoimmune conditions: Theoretical concern due to immunomodulatory effects
• Thyroid disorders: May increase thyroid hormone levels; monitor thyroid function
• Medication interactions:
  • May potentiate sedative medications
  • Potential interaction with thyroid medications
  • May affect blood glucose levels in diabetic patients

Monitoring Recommendations

• Monitor for improvement in target symptoms (stress, anxiety, sleep)
• No specific laboratory monitoring required in healthy individuals
• Consider thyroid function testing in patients with pre-existing thyroid conditions
• Discontinue if significant adverse effects occur

Quality Considerations

• Choose products standardized to withanolide content (2.5-5%)
• Select reputable manufacturers with quality control testing
• Full-spectrum extracts may provide better results than isolated compounds

Ashwagandha appears to be a safe and effective adaptogenic herb when used at appropriate doses for managing stress, anxiety, and improving general well-being. The clinical evidence supports its use as a complementary approach for these conditions.