Diltiazem Is Not Effective for Treating Epilepsy
Diltiazem (calcium channel blocker) is not recommended for treating epilepsy as there is no evidence supporting its efficacy as an antiseizure medication, and it may actually shorten seizure duration, potentially making treatments like electroconvulsive therapy less effective 1.
Evidence Regarding Diltiazem and Epilepsy
Mechanism and Classification
Diltiazem is a non-dihydropyridine calcium channel blocker (CCB) that:
- Selectively inhibits voltage-gated L-type channels on cardiac myocytes and vascular smooth muscle cells 2
- Has greater selectivity for myocardial cells, resulting in decreased sinoatrial and atrioventricular node conduction and decreased myocardial contractility 2
- Is primarily indicated for hypertension, chronic stable angina, and supraventricular arrhythmias 2
Lack of Evidence for Epilepsy Treatment
- None of the major epilepsy treatment guidelines list diltiazem among recommended antiseizure medications (ASMs) 3
- The American Academy of Neurology's practice guideline for treating new-onset epilepsy does not include diltiazem among recommended treatments 3
- First-line treatments for focal epilepsy include oxcarbazepine and lamotrigine, while generalized epilepsy treatment depends on the specific syndrome 4
Potential Negative Effects on Seizures
- Diltiazem has been shown to significantly reduce seizure duration during electroconvulsive therapy, potentially making this treatment less effective 1
- This suggests that rather than helping control seizures, diltiazem might actually interfere with therapeutic seizure activity in certain contexts
Established Antiseizure Medications
The FDA has approved 26 medications specifically for epilepsy treatment 4:
- 24 have similar efficacy for focal epilepsy
- 9 have similar efficacy for generalized epilepsy
- Selection should be based on seizure type, epilepsy syndrome, and potential adverse effects
First-line Options for Epilepsy
- For focal epilepsy: oxcarbazepine and lamotrigine are first-line therapy, with levetiracetam as an alternative (unless there is psychiatric history) 4
- For generalized epilepsy: medication selection depends on epilepsy syndrome, patient's sex, age, and psychiatric history 4
Potential Anticonvulsant Properties of Some Cardiovascular Drugs
While diltiazem itself is not recommended for epilepsy treatment, it's worth noting that some studies have suggested certain cardiovascular medications may have anticonvulsant properties in experimental models:
- Some calcium channel blockers including isradipine, nimodipine, verapamil, and diltiazem have shown anticonvulsant effects in animal models 5
- Verapamil and diltiazem showed "moderate anticonvulsant activity" in genetically epilepsy-prone rats 6
However, these experimental findings have not translated to clinical recommendations for using diltiazem as an antiseizure medication in humans with epilepsy.
Clinical Considerations and Cautions
When treating patients who have both epilepsy and cardiovascular conditions:
- Drug-drug interactions between antiseizure medications and cardiovascular drugs must be carefully considered 5
- Enzyme-inducing antiseizure medications can interact with calcium channel blockers like diltiazem 5
- The combination of beta-blockers with non-dihydropyridine calcium channel blockers (like diltiazem) significantly increases the risk of bradycardia and heart block 7
Conclusion
Based on current evidence, diltiazem should not be used for the treatment of epilepsy. Patients with epilepsy should be treated with FDA-approved antiseizure medications that have demonstrated efficacy in clinical trials. If a patient has both epilepsy and a cardiovascular condition requiring diltiazem, careful monitoring for drug interactions is essential, but diltiazem itself should not be expected to provide seizure control.