Diltiazem and Iloperidone interaction
Diltiazem and Iloperidone: the Iloperidone prescribing label describes 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 Iloperidone (FANAPT) label · effective 2026-05-06
…FANAPT should be avoided in combination with other drugs that are known to prolong QTc including Class 1A (e.g., quinidine, procainamide) or Class III (e.g., amiodarone, sotalol) antiarrhythmic medications, antipsychotic medications (e.g., chlorpromazine, thioridazine), antibiotics (e.g., gatifloxacin, moxifloxacin), or any other class of medications known to…
Orthostatic vital signs should be monitored in patients who are vulnerable to hypotension (e.g., elderly patients, patients with dehydration, hypovolemia, and concomitant treatment with antihypertensive medications), patients with known cardiovascular disease (history of myocardial infarction, ischemic heart disease, heart failure, or conduction abnormalities), and…
The dose of FANAPT should be reduced in patients co-administered a strong CYP2D6 or CYP3A4 inhibitor.
Strong CYP3A4 Inhibitors Clinical Impact Co-administration of ketoconazole with iloperidone, increased the AUC of iloperidone and its metabolites P88 and P95 by 57%, 55%, and 35%, respectively [see Clinical Pharmacology (12.3) ] .
Intervention Reduce the dose of FANAPT by one-half when administered with strong CYP3A4 inhibitors.
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.