Supplement stacks / Mirtazapine + St Johns Wort

Can You Take Mirtazapine with St Johns Wort?

Combining St. John's Wort with mirtazapine may lead to reduced effectiveness of mirtazapine due to St. John's Wort's induction of certain liver enzymes. This combination could potentially increase the risk of side effects or reduce therapeutic effects. Caution is advised, and consultation with a healthcare provider is essential.

Safety at a glance
High risk
Safety score4/10

Conservative, AI-assisted reading of publicly available medical sources (NIH, Mayo Clinic, WebMD, Examine.com). Informational only — it can't account for your medications, conditions, or genetics.

Known interactions
Mirtazapine

Generally well-tolerated; however, it can cause sedation and weight gain.

Typical dosage: 15-45 mg daily, taken at bedtime

Common side effects:
  • Drowsiness
  • Increased appetite
  • Dry mouth
Warnings:
  • Monitor for increased sedation or side effects when combined with other sedatives.
St. John's Wort

Generally considered safe for short-term use; however, it can interact with various medications.

Typical dosage: 300-900 mg daily, divided into doses

Common side effects:
  • Gastrointestinal upset
  • Fatigue
  • Allergic skin reactions
Warnings:
  • May interact with antidepressants, including mirtazapine; consult healthcare provider before use.
Also commonly mentioned

These come up in questions about this combination — they are not part of the pair above.

Omega-3 Fatty Acids

Generally safe; may support mood and cognitive function.

Typical dosage: 1000-3000 mg daily

Common side effects:
  • Fishy aftertaste
  • Gastrointestinal discomfort
Warnings:
  • Consult healthcare provider if on anticoagulants.

L-Theanine

Considered safe; may promote relaxation without sedation.

Typical dosage: 100-400 mg daily

Common side effects:
  • Headache
  • Dizziness
Warnings:
  • Consult healthcare provider if taking other medications affecting mood.

Vitamin D3

Generally safe; important for overall health and mood regulation.

Typical dosage: 600-2000 IU daily

Common side effects:
  • Nausea
  • Constipation
Warnings:
  • Monitor levels if taking high doses; consult healthcare provider.
Timing

St. John's Wort should be taken consistently at the same time each day to maintain stable levels in the body. Mirtazapine is typically taken at bedtime due to its sedative effects.

Watch out for
  • Avoid combining St. John's Wort with mirtazapine without consulting a healthcare provider due to potential interactions.
Frequently asked questions

Can you take Mirtazapine and St Johns Wort together?

Combining St. John's Wort with mirtazapine may lead to reduced effectiveness of mirtazapine due to St. John's Wort's induction of certain liver enzymes. This combination could potentially increase the risk of side effects or reduce therapeutic effects. Caution is advised, and consultation with a healthcare provider is essential.

How safe is the Mirtazapine and St Johns Wort combination?

Our analysis of publicly available medical sources scores this combination 4/10 (high risk). This is an informational estimate, not medical advice — always confirm with a healthcare professional.

When should you take Mirtazapine and St Johns Wort?

St. John's Wort should be taken consistently at the same time each day to maintain stable levels in the body. Mirtazapine is typically taken at bedtime due to its sedative effects.

What should you watch out for when combining Mirtazapine and St Johns Wort?

Avoid combining St. John's Wort with mirtazapine without consulting a healthcare provider due to potential interactions.

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Analysis generated August 11, 2026 · Sources include NIH, Mayo Clinic, WebMD, and Examine.com · How our analysis works