Drug interactions
Lisdexamfetamine + St john's wort
Severity: Major
Lisdexamfetamine and St john's wort: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
St John's wort has serotonergic activity and amphetamines also increase synaptic serotonin, so combining them may raise the risk of serotonin syndrome. Symptoms include agitation, tremor, hyperthermia, diarrhea and neuromuscular abnormalities.
What this interaction means in plain words
Lisdexamfetamine and St john's wort can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Additive serotonergic effects: amphetamine-induced serotonin release with reuptake inhibition from the herbal product.
What to do
Avoid the combination where possible and ask about herbal supplements before starting lisdexamfetamine. If used together, monitor for serotonin syndrome and stop the serotonergic agents if it develops.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Lisdexamfetamine
- Isocarboxazid + Lisdexamfetamine Contraindicated
- Linezolid + Lisdexamfetamine Contraindicated
- Lisdexamfetamine + Phenelzine Contraindicated
- Lisdexamfetamine + Procarbazine Contraindicated
- Lisdexamfetamine + Rasagiline Contraindicated
- Lisdexamfetamine + Safinamide Contraindicated
Frequently asked questions
Can I take Lisdexamfetamine with St john's wort?
MediHelp rates the interaction as major. Lisdexamfetamine and St john's wort can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. St John's wort has serotonergic activity and amphetamines also increase synaptic serotonin, so combining them may raise the risk of serotonin syndrome. Symptoms include agitation, tremor, hyperthermia, diarrhea and neuromuscular abnormalities.
How serious is the interaction between Lisdexamfetamine and St john's wort?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible and ask about herbal supplements before starting lisdexamfetamine. If used together, monitor for serotonin syndrome and stop the serotonergic agents if it develops.
What other medicines interact with Lisdexamfetamine?
MediHelp also lists interactions of Lisdexamfetamine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Lisdexamfetamine page.
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