In this episode, I’ll discuss what works best for toxin-related status epilepticus.
While benzodiazepines are first line treat for status epilepticus, they do not work in as many as one-third of patients. Early termination of convulsive status epilepticus is important because it lowers the chance of cardiac and respiratory issues as well as the risk of admission to the ICU.
The ideal treatment for benzodiazepine-refractory status epilepticus was not studied very well until the 2019 publication in NEJM of a Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus. This trial compared the efficacy and safety of three intravenous anticonvulsive agents – levetiracetam, fosphenytoin, and valproate in children and adults with convulsive status epilepticus that was unresponsive to treatment with benzodiazepines.
In the NEJM study, each of the three medications led to seizure cessation and improved alertness by 60 minutes in approximately half the patients, and the three medications were associated with similar incidences of adverse events.
Recently, in the journal Annals of Emergency Medicine, a group of authors reported an analysis of the 2019 NEJM article looking at the subset of patients who had a toxin-related seizure as the precipitating seizure that developed into status epilepticus. Toxin-related seizures occurred in 29 adults and 1 child in the study population. Alcohol withdrawal and cocaine use were the most common toxins implicated, with each responsible for 11 episodes of benzodiazepine resistant status epilepticus.
The success rates for alcohol withdrawal-related seizures were as follows:
Levetiracetam – 3 of 3 patients
Valproate – 3 of 6 patients
Fosphenytoin – 1 of 2 patients
The success rates for cocaine-related seizures were as follows:
Levetiracetam – 1 of 7 patients
Valproate – 0 of 1 patients
Fosphenytoin – 1 of 3 patients
Other causes of seizure included 4 patients with alcohol toxicity, 1 benzodiazepine withdrawal, 1 diphenhydramine toxicity, 1 amlodipine toxicity, and 1 amphetamine toxicity.
The authors noted that levetiracetam is the most attractive option for the treatment of toxin-related status epilepticus, however all 3 medications studied seemed to have poor efficacy against cocaine-precipitated status epilepticus. Barbituates, propofol, and ketamine were not studied at all in this trial.
As far as serious adverse effects, the authors of the report note that a patient who used cocaine and an opioid received fosphenytoin and experienced life-threatening hypotension.
Overall, toxin-related status epilepticus was terminated with a single dose of antiepileptic 42% of the time. Until better data is available pharmacists can use this information to select treatments and predict efficacy for patients with toxin-related status epilepticus.
To access my free download area with 20 different resources to help you in your practice, go to pharmacyjoe.com/free.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.