Lithium and Risperidone interaction
Lithium and Risperidone: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Lithium (Lithium Carbonate) label · effective 2026-06-04
• Encephalopathic Syndrome: Increased risk in patients treated with lithium and an antipsychotic.
Because of a possible causal relationship between these events and the concomitant administration of lithium and antipsychotics, patients receiving such combined treatment should be monitored closely for early evidence of neurological toxicity and treatment discontinued promptly if such signs appear.
Atypical and Typical Antipsychotic Drugs Clinical Impact: Reports of neurotoxic reactions in patients treated with both lithium and an antipsychotic, ranging from extrapyramidal symptoms to neuroleptic malignant syndrome, as well as reports of an encephalopathic syndrome in few patients treated with concomitant therapy [see Warnings and Precautions ( 5.5 )] .
Encephalopathic Syndrome An encephalopathic syndrome, characterized by weakness, lethargy, fever, tremulousness and confusion, extrapyramidal symptoms, leukocytosis, elevated serum enzymes, BUN and fasting blood glucose, has occurred in patients treated with lithium and an antipsychotic.
This encephalopathic syndrome may be similar to or the same as neuroleptic malignant syndrome (NMS).
From the Risperidone (RISPERDAL CONSTA) label · effective 2025-11-05
Lithium Repeated doses of oral RISPERDAL (3 mg twice daily) did not affect the exposure (AUC) or peak plasma concentrations (C max ) of lithium (N=13).
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.