Drug class·SNRIs·Reviewed June 9, 2026
SNRIs and supplements: same serotonin caution, plus blood pressure.
SNRIs share the SSRI serotonin-stacking caution (St John's wort, 5-HTP) and add a norepinephrine side that can nudge blood pressure, which matters when stacking stimulants. The documented interactions for each SNRI are below.
SNRIs at a glance.
A quick, data-grounded summary. The per-drug tables are below.
Across the 3 SNRIs in the NutriStack database (Duloxetine, Venlafaxine, and Desvenlafaxine), 6 substances have a documented interaction, 4 of them flagged to avoid or as a serious conflict. Long-term use of some medications in this class is also associated with lower Sodium; the depletion table shows exactly which drugs. Interactions are documented per drug, and members of a class do not all behave the same, so check your exact medication below. None of this replaces your prescriber's advice.
The SNRIs we track.
Open any medication for its own full interaction and depletion guide.
Substances that interact with SNRIs.
Merged across the class, highest severity first. The 'Documented for' column shows which members carry the interaction record; an absent drug means no documented record, not proven safety.
| Substance | Interaction | Documented for | What happens |
|---|---|---|---|
| 5-HTP | Contraindicated | All 3 SNRIs | Duloxetine: Duloxetine is a serotonin-norepinephrine reuptake inhibitor (SNRI) that potently blocks serotonin reuptake. Adding 5-HTP, a direct... |
| L-Tryptophan | Contraindicated | All 3 SNRIs | Duloxetine: Duloxetine blocks both serotonin and norepinephrine reuptake, and L-tryptophan provides extra substrate for serotonin synthesis. The... |
| MDMA | Contraindicated | All 3 SNRIs | Duloxetine: Duloxetine directly interferes with MDMA pharmacology at serotonin and norepinephrine transporters. In a controlled human study,... |
| St. John's Wort | Contraindicated | All 3 SNRIs | Duloxetine: Combining duloxetine (an SNRI) with St. John's Wort creates a serious risk of serotonin syndrome. Both agents increase synaptic serotonin... |
| SAMe | Caution | Duloxetine, Venlafaxine | Duloxetine: SAMe has antidepressant and monoamine-modulating activity. Duloxetine increases serotonin and norepinephrine signaling, so adding SAMe may... |
| Alcohol | Caution | Duloxetine | Duloxetine has a known rare risk of clinically significant liver injury, and substantial alcohol use is a recognized risk factor in... |
What SNRIs can deplete.
Nutrients associated with long-term use somewhere in this class, worst documented severity first. Discuss any replacement with your prescriber.
| Nutrient | Severity | Documented for | Replace with | Monitor |
|---|---|---|---|---|
| Sodium | Moderate | All 3 SNRIs | – | Serum sodium |
Common SNRIs questions.
Quick answers drawn from the tables above.
What supplements should I avoid with SNRIs?
Across the class, 4 substance pairings are flagged to avoid or as a serious conflict, including 5-HTP, L-Tryptophan, MDMA, and St. John's Wort. The exact risk depends on which medication in the class you take, so check your specific drug's page and confirm with your prescriber.
Do all SNRIs interact with supplements the same way?
No. Interactions are documented per drug, and the 3 SNRIs in the database differ in how they are absorbed and cleared. The class table above shows which members carry each record; a drug without a record is undocumented, not proven safe.
Do SNRIs deplete any nutrients?
Some medications in this class are documented to lower Sodium with long-term use; the depletion table on this page shows which specific drugs carry each record. Useful biomarkers to monitor include Serum sodium. Ask your prescriber before adding a replacement supplement.
Is it safe to take 5-HTP with SNRIs?
NutriStack classifies the 5-HTP and Duloxetine pairing as contraindicated: Duloxetine is a serotonin-norepinephrine reuptake inhibitor (SNRI) that potently blocks serotonin reuptake. Adding 5-HTP, a direct serotonin precursor, significantly... The interaction is documented for 3 of the 3 SNRIs, and severity differs by drug. Always confirm with your prescriber.
Check your whole stack
See how your medication fits your supplements.
NutriStack screens your full routine for interactions and depletions, and updates the moment you change it.