What the FDA labels say about taking them together
Lithium and venlafaxine
Venlafaxine's FDA label of August 15, 2023 names lithium in its drug interactions section; lithium's label does not name venlafaxine itself but warns about its class (SNRIs (serotonin and norepinephrine reuptake inhibitors)). The venlafaxine label: “Caution when using venlafaxine with such drugs. Serotonergic drugs: Potential for serotonin syndrome.”
Check it at the source: the lithium FDA label on DailyMed (effective December 23, 2025, Glenmark Pharmaceuticals Inc., USA); the venlafaxine FDA label on DailyMed (effective August 15, 2023, Viatris Specialty LLC).
What does the lithium label say about venlafaxine?
Lithium's label does not name venlafaxine itself; it warns about its class (SNRIs (serotonin and norepinephrine reuptake inhibitors)):
Lithium label, warnings and precautionsThe risk is increased with concomitant use of other serotonergic drugs (including selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, triptans, tricyclic antidepressants, fentanyl, tramadol, tryptophan, buspirone, and St. John’s Wort) and with drugs that impair metabolism of serotonin, i.e., MAOIs [see Drug Interactions ( 7.1 )].
Source: FDA drug label (Lithium Carbonate), Glenmark Pharmaceuticals Inc., USA, effective December 23, 2025 (SPL set 63b3790f-a9b5-47f4-bae1-ddf8b43c13c1), via openFDA; the full label on DailyMed
What does the venlafaxine label say about lithium?
Venlafaxine label, drug interactionsClinical Impact; Concomitant use of Effexor XR with other serotonergic drugs (including other SNRIs, SSRIs, triptans, tricyclic antidepressants, opioids, lithium, buspirone, amphetamines, tryptophan, and St. John's Wort) increases the risk of serotonin syndrome.
Venlafaxine label, warnings and precautionsThe risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, meperidine, methadone, tryptophan, buspirone, amphetamines, and St. John’s Wort) and with drugs that impair metabolism of serotonin, i.e., MAOIs [see Contraindications (4), Drug Interactions (7.1) ].
Venlafaxine Hydrochloride label (Trigen Laboratories, LLC, July 31, 2025), drug interactionsCaution when using venlafaxine with such drugs. ( 7.10 ) Serotonergic drugs (e.g., triptans, SSRIs, other SNRIs, linezolid, lithium, tramadol, or St. John's Wort): Potential for serotonin syndrome.
Source: FDA drug label (Venlafaxine, NDA215429), Almatica Pharma LLC, effective October 9, 2025 (SPL set e81a2daf-b8b2-7c05-b532-bc775700b100), via openFDA
Source: FDA drug label (Venlafaxine Hydrochloride, NDA022104), Trigen Laboratories, LLC, effective July 31, 2025 (SPL set fdaed1c2-dd0a-4bf3-975a-86fe3e7f0c97), via openFDA
Source: FDA drug label (Effexor XR), NDA020699 (Upjohn), as published by Viatris Specialty LLC, effective August 15, 2023 (SPL set c848a5d8-ba94-4c84-80e3-0bf35fb8e32e), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Lithium | Venlafaxine | |
|---|---|---|
| Labeled for | Bipolar disorder | Depression, Anxiety |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.104 per capsule 300 mg capsule | $0.0799 per capsule 75 mg capsule |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once