Nitroglycerin is NOT indicated for seizure management and should be avoided
Nitroglycerin (NTG) has no role in the treatment of seizures and is potentially harmful in this context. The evidence base for NTG is exclusively focused on cardiac ischemia, acute coronary syndromes, and hypertensive emergencies—not neurological emergencies like seizures 1.
Why NTG Should Not Be Used in Seizures
Lack of Therapeutic Rationale
- NTG is a vasodilator that reduces myocardial oxygen demand and enhances coronary blood flow through venodilation and arterial dilation 1, 2
- Its mechanism of action addresses cardiac ischemia, not the neuronal hyperexcitability that underlies seizure activity 1
- No guidelines or evidence support NTG use for seizure management 3, 4
Potential Harm in Neurological Emergencies
- NTG's vasodilatory effects can cause a "steal phenomenon" where blood flow is diverted away from ischemic brain areas, potentially worsening neurological injury 5
- Hypotension induced by NTG can reduce cerebral perfusion pressure in already compromised brain tissue 5
- Cerebral vasodilation from NTG may worsen cerebral edema and increase intracranial pressure 5
- In one case report, NTG overdose was associated with tonic-clonic seizures as a toxic effect, not as a therapeutic indication 6
Hemodynamic Risks
- NTG commonly causes hypotension, which is particularly dangerous in acute neurological conditions where maintaining adequate cerebral perfusion is critical 5
- The drug can cause significant drops in blood pressure that may extend areas of brain ischemia 5
- NTG is contraindicated when systolic blood pressure is below 90 mmHg or more than 30 mmHg below baseline 1, 5
Appropriate Seizure Management
First-Line Treatment
- Benzodiazepines (lorazepam, diazepam, midazolam) are the agents of first choice for acute seizure management 3, 4
- Intramuscular midazolam is easier than intravenous lorazepam in pre-hospital settings 4
Second-Line Agents
- If seizures continue despite benzodiazepines, use valproate, levetiracetam, phenobarbital, or fosphenytoin 3, 4
- Guidelines recommend lorazepam followed by fosphenytoin (or phenytoin if fosphenytoin unavailable) for status epilepticus 4
Special Consideration
- If hyponatremia is the underlying cause of seizures, treat with 3% hypertonic saline in combination with anticonvulsants, not vasodilators 7
The only documented association between NTG and seizures is as a toxic effect from massive overdose, not as a therapeutic intervention 6.