What the FDA labels say about taking them together
Rifampin and risperidone
Risperidone's FDA label (Risperdal Consta) of November 5, 2025 names rifampin in its drug interactions section; the rifampin label PlainMeds reads does not name risperidone. The risperidone label: “Co-administration of other known CYP 3A4 enzyme inducers with risperidone may cause similar decreases in the combined plasma concentrations of risperidone and 9-hydroxyrisperidone, which could lead to decreased efficacy …”
Check it at the source: the rifampin FDA label on DailyMed (effective February 11, 2026, Lupin Pharmaceuticals, Inc.); the risperidone FDA label on DailyMed (effective May 28, 2026, Janssen Pharmaceuticals, Inc.).
What does the rifampin label say about risperidone?
Rifampin's label (effective February 11, 2026) does not name risperidone in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (rifampin), Lupin Pharmaceuticals, Inc., effective February 11, 2026 (SPL set b56004f0-f23d-47f6-80c7-39884fccbccc), via openFDA; the full label on DailyMed
What does the risperidone label say about rifampin?
Risperdal Consta label (Janssen Pharmaceuticals, Inc., November 5, 2025), drug interactionsCo-administration of other known CYP 3A4 enzyme inducers (e.g., phenytoin, rifampin, and phenobarbital) with risperidone may cause similar decreases in the combined plasma concentrations of risperidone and 9-hydroxyrisperidone, which could lead to decreased efficacy of RISPERDAL CONSTA treatment.
Source: FDA drug label (Risperdal Consta, NDA021346), Janssen Pharmaceuticals, Inc., effective November 5, 2025 (SPL set bb34ee82-d2c2-43b8-ba21-2825c0954691), via openFDA
Source: FDA drug label (RISPERDAL), Janssen Pharmaceuticals, Inc., effective May 28, 2026 (SPL set 7e117c7e-02fc-4343-92a1-230061dfc5e0), 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
| Rifampin | Risperidone | |
|---|---|---|
| Labeled for | n/a | Bipolar disorder, Schizophrenia |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.679 per capsule 300 mg capsule | $0.0368 per tablet 0.25 mg tablet |
| Shortage now | In shortage | 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