Supplement stacks / L-Theanine + St Johns Wort
Can You Take L-Theanine with St Johns Wort?
L-Theanine and St Johns Wort: one interaction flagged, scored 7/10 (medium risk). The count and score come from an AI-written analysis checked against our interaction rules, which can only make it stricter. Not medical advice.
Safety at a glance
This score comes from an AI-written analysis of the pair. Our interaction rules check it and can only make it stricter, never milder. Informational only: it can't account for your medications, conditions, or genetics.
What the AI-written analysis says
L-Theanine and St. John's Wort can be taken together, but caution is advised due to potential interactions with other medications, particularly those affecting serotonin levels. L-Theanine is generally safe with moderate evidence supporting its use, while St. John's Wort has limited evidence and known interactions with various medications.
Known interactions
Both supplements may influence serotonin levels, but specific interactions are not well-documented.
L-Theanine
From the AI-written analysis.
Generally considered safe with few reported side effects. Rarely, it may cause gastrointestinal discomfort.
Typical dosage: 100-200 mg daily
- Headache
- Dizziness
- Gastrointestinal upset
- May enhance the effects of caffeine; monitor intake if consuming caffeinated products.
- Consult healthcare provider if taking other medications.
St. John's Wort
From the AI-written analysis.
Generally safe for short-term use, but can interact with many medications, including antidepressants and anticoagulants.
Typical dosage: Follow manufacturer guidelines
- Dry mouth
- Dizziness
- Fatigue
- Gastrointestinal symptoms
- Consult healthcare provider before use, especially if taking other medications.
- May cause photosensitivity; use sunscreen.
Also commonly mentioned
These come up in questions about this combination. They are not part of the pair above. From the AI-written analysis.
Caffeine
Generally safe in moderate amounts; excessive intake can lead to anxiety and insomnia.
Typical dosage: 200-400 mg daily
- Insomnia
- Nervousness
- Restlessness
- Stomach upset
- Limit intake if sensitive to caffeine; monitor for increased anxiety when combined with L-Theanine.
SSRIs (Selective Serotonin Reuptake Inhibitors)
Effective for depression and anxiety but can lead to serotonin syndrome if combined with other serotonergic agents.
Typical dosage: Varies by specific medication
- Nausea
- Weight gain
- Sexual dysfunction
- Monitor for signs of serotonin syndrome if taking St. John's Wort with SSRIs.
Anticoagulants (e.g., Warfarin)
Effective for preventing blood clots but requires careful monitoring.
Typical dosage: As prescribed or as directed on the label
- Bleeding
- Bruising
- Gastrointestinal upset
- Monitor INR more frequently if taking St. John's Wort, as it may reduce effectiveness.
Timing
L-Theanine can be taken at any time of day, while St. John's Wort may require consistent timing for effectiveness.
Watch out for
- Consult a healthcare provider before combining these supplements, especially if on other medications.
- Monitor for any unusual side effects or changes in mood.
Frequently asked questions
Can you take L-Theanine and St Johns Wort together?
L-Theanine and St Johns Wort: one interaction flagged, scored 7/10 (medium risk). The count and score come from an AI-written analysis checked against our interaction rules, which can only make it stricter. Not medical advice.
What score does the L-Theanine and St Johns Wort combination get?
The L-Theanine and St Johns Wort combination is scored 7/10 (medium risk). The score comes from an AI-written analysis checked against our interaction rules, which can only make it stricter. Not medical advice. Always confirm with a healthcare professional.
When should you take L-Theanine and St Johns Wort?
L-Theanine can be taken at any time of day, while St. John's Wort may require consistent timing for effectiveness.
What should you watch out for when combining L-Theanine and St Johns Wort?
Consult a healthcare provider before combining these supplements, especially if on other medications. Monitor for any unusual side effects or changes in mood.
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Not medical advice
AI-written analysis generated August 11, 2026, checked by our interaction rules · How our analysis works