Drug interactions
Dextroamphetamine + Fluoxetine
Severity: Major
Dextroamphetamine and Fluoxetine: major interaction.
Last updated Sources: US FDA label
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
Fluoxetine inhibits CYP2D6 and can raise dextroamphetamine exposure, and both drugs enhance serotonergic and sympathomimetic activity. This increases the risk of serotonin syndrome, hypertension, tachycardia and agitation.
What this interaction means in plain words
Dextroamphetamine and Fluoxetine 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.
Dextroamphetamine belongs to Central Nervous System; Fluoxetine belongs to Central Nervous System.
Why it happens
Fluoxetine inhibits CYP2D6-mediated amphetamine metabolism, and both agents increase synaptic serotonin.
What to do
Start dextroamphetamine at a low dose and titrate slowly while monitoring for serotonin syndrome features, blood pressure and heart rate. Stop the serotonergic agents and treat supportively if serotonin toxicity 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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References
Other interactions of Fluoxetine
- Fluoxetine + Isocarboxazid Contraindicated
- Fluoxetine + Mavacamten Contraindicated
- Fluoxetine + Methylene blue Contraindicated
- Fluoxetine + Phenelzine Contraindicated
- Fluoxetine + Pimozide Contraindicated
- Fluoxetine + Rasagiline Contraindicated
Other interactions of Dextroamphetamine
- Dextroamphetamine + Isocarboxazid Contraindicated
- Dextroamphetamine + Linezolid Contraindicated
- Dextroamphetamine + Methylene blue Contraindicated
- Dextroamphetamine + Phenelzine Contraindicated
- Dextroamphetamine + Rasagiline Contraindicated
- Dextroamphetamine + Safinamide Contraindicated
Frequently asked questions
Can I take Dextroamphetamine with Fluoxetine?
MediHelp rates the interaction as major. Dextroamphetamine and Fluoxetine 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. Fluoxetine inhibits CYP2D6 and can raise dextroamphetamine exposure, and both drugs enhance serotonergic and sympathomimetic activity. This increases the risk of serotonin syndrome, hypertension, tachycardia and agitation.
How serious is the interaction between Dextroamphetamine and Fluoxetine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Start dextroamphetamine at a low dose and titrate slowly while monitoring for serotonin syndrome features, blood pressure and heart rate. Stop the serotonergic agents and treat supportively if serotonin toxicity develops.
What other medicines interact with Fluoxetine?
MediHelp also lists interactions of Fluoxetine with, for example, Isocarboxazid, Mavacamten, Methylene blue. The full list is on the Fluoxetine page.
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