Isradipine
Antihypertensive (calcium channel blocker)
- Mania/mixed [4]
- Ultra-rapid cycling [3]
Features
Dosing
Bipolar: 5-20mg/day, divided BID (typical 2.5mg bid, or use XR)
INTERACTIONS: CYP3A4 inducers/inhibitors alter its levels (including grapefruit which raises it).
Management
Possibly treats mania, rapid cycling (4 episodes per year) and ultra-rapid cycling (more frequent). Similar to nimodipine and amlodipine, while verapamil has a different mechanism.
TOLERABILITY: Dizziness, GI upset, rare edema.
RISKS: Get medical approval in heart disease (AV conduction delays). Monitor BP (hypotension risk). Very rare LFT elevation.
EMR Text
Bipolar Rapid Cycling
Isradipine use based on small trials in bipolar disorder and larger body of evidence for this class in bipolar (Ostacher MJ et al, Bipolar Disord. 2014;16(2):199-203)
Off label use and cardiac risks (hypotension) reviewed with patient.