What are the contraindications for ashwagandha (Withania somnifera)?

Contraindications for Ashwagandha (Withania somnifera)

Ashwagandha is contraindicated in pregnancy, nursing mothers, autoimmune conditions, hyperthyroidism, and when taking sedative medications, MAOIs, or medications with narrow therapeutic windows that interact with CYP3A4 or CYP2D6. 1

Absolute Contraindications

• Pregnancy and breastfeeding: Ashwagandha may pose risks to the fetus or infant 1
• Autoimmune diseases: Including rheumatoid arthritis, lupus, and Hashimoto's thyroiditis 1
• Hyperthyroidism: Due to potential effects on thyroid function 1
• Medication interactions:
  • Monoamine oxidase inhibitors (MAOIs) 1
  • Sedative medications (due to additive effects) 1
  • Benzodiazepines and barbiturates (potentiates sedation) 1

Relative Contraindications/Precautions

• Pre-surgical periods: Should be discontinued at least 2 weeks before scheduled surgery due to:

  • Sedative properties that may interact with anesthesia
  • Potential increased bleeding risk
  • Possible interference with blood pressure control during surgery 1

• Liver conditions: Cases of ashwagandha-induced liver injury have been reported, presenting as cholestatic or mixed hepatitis with jaundice and pruritus 2

• Neurological disorders: Use with caution due to potential sedative effects 1

• Drug interactions: Ashwagandha may interact with medications metabolized by CYP3A4 and CYP2D6, though some studies suggest minimal inhibition of these enzymes 3

Monitoring Recommendations

For patients taking ashwagandha, the following should be monitored:

• Thyroid function: In patients with thyroid disorders 1
• Blood pressure: In patients with cardiovascular conditions 1
• Blood glucose: In diabetic patients 1
• Signs of excessive sedation: When combined with other medications 1
• Liver function: Monitor for signs of jaundice, pruritus, nausea, lethargy, and abdominal discomfort 2

Adverse Effects to Watch For

• Common adverse effects (>5%): Somnolence, epigastric discomfort, loose stools 3
• Less common adverse effects: Giddiness, drowsiness, hallucinations, vertigo, nasal congestion, cough, cold, decreased appetite, nausea, constipation, dry mouth, hyperactivity, nocturnal cramps, blurred vision, hyperacidity, skin rash, and weight gain 3
• Liver injury: Typically cholestatic or mixed with severe jaundice and pruritus, usually self-limited with normalization of liver tests in 1-5 months 2

Special Considerations

• QT prolongation risk: While ashwagandha itself has not been specifically linked to QT prolongation, caution is advised when combining with medications known to prolong QT interval 4

• Increased appetite and libido: These effects have been reported in some individuals and may be undesirable in certain patient populations 5

While many studies have shown ashwagandha to be generally well-tolerated 6, clinicians should be aware of these contraindications and exercise appropriate caution, particularly in vulnerable populations or those taking multiple medications.