Lithium Carbonate and Meperidine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Meperidine
Lithium Carbonate
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased risk of serotonin syndrome
Interaction Deep Dive
Meperidine is considered a proserotonergic opioid and has been associated with serotonin syndrome when used concomitantly with other serotonergic agents5. If concomitant use of meperidine and serotonergic agents is necessary, observe the patient especially during treatment initiation and dose adjustment. Symptoms of serotonin syndrome generally occur within hours to days of use 23. Symptoms of serotonin syndrome include neuromuscular abnormalities (hyperreflexia, tremor, muscle rigidity, clonus, peripheral hypertonicity, and shivering), autonomic hyperactivity (tachycardia, mydriasis, diaphoresis, the presence of bowel sounds, and diarrhea), and mental status changes (including agitation and delirium). Serotonin syndrome can be life-threatening. Discontinue the offending agents, if serotonin syndrome develops and provide supportive care therapy as necessary 14.
Why it happens (mechanism)
Additive serotonergic effects
Literature reports
2 reports — tap to read
a) Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of meperidine with serotonergic drugs 234.
b) Meperidine is considered a proserotonergic opioid and has been associated with serotonin syndrome when used concomitantly with other serotonergic agents 5.
Common questions
Can I take Lithium Carbonate and Meperidine together?
Increased risk of serotonin syndrome Always confirm with your pharmacist or prescriber before making any change.
How serious is the Lithium Carbonate and Meperidine interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Lithium Carbonate or Meperidine need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (5)
- Boyer EW & Shannon M: The serotonin syndrome. N Eng J Med 2005; 352(11):1112-1120. PubMed
- Product Information: MEPERGAN intramuscular, intravenous injection, meperidine HCl, promethazine HCl intramuscular, intravenous injection. West-Ward Pharmaceuticals Corp (per FDA), Eatontown, NJ, 2023.
- Product Information: DEMEROL(R) oral tablets, oral solution, meperidine HCl oral tablets, oral solution. Validus Pharmaceuticals LLC (per FDA), Parsippany, NJ, 2023. DailyMed
- Product Information: Demerol(TM) intramuscular, subcutaneous, intravenous injection, meperidine HCl intramuscular, subcutaneous, intravenous injection. Hospira Inc (per FDA), Lake Forest, IL, 2022.
- Rastogi R, Swarm RA, & Patel TA: Case scenario: opioid association with serotonin syndrome: implications to the practitioners. Anesthesiology 2011; 115(6):1291-1298. PubMed
Keep reading about Meperidine
Keep reading about Lithium Carbonate
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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