Levodropropizine suppresses seizure activity in rats with pentylenetetrazol-induced epilepsy

Millions of individuals worldwide suffer from epilepsy, and up to 25% of patients have seizures that are resistant to currently available antiepileptic drugs. Hence, there continues to be a need for more seizure medications that are effective yet tolerable. Levodropropizine (LVDP) is an established antitussive drug that, based on preclinical data, may also have antiepileptic activity.

We treated rats with either intraperitoneal (IP) LVDP at two different doses or placebo in randomized fashion and then exposed them to IP pentylenetetrazol (PTZ), a potent seizure-inducing compound. We measured the rats' subsequent seizure activity with electroencephalography (EEG), Racine's convulsion scale (RCS) and time to first myoclonic jerk (TFMJ) to determine whether LVDP has antiepileptic properties in our murine model for epilepsy.

When compared to placebo, LVDP at both doses significantly suppressed seizure activity. Mean EEG spike wave percentage score decreased from 76.8% (placebo) to 13.1% (lower dose) and 7.6% (higher dose, bothp <  0.0001). RCS decreased from a mean of 5.8 (placebo) to 1.83 (lower dose) and 1.16 (higher dose, both p <  0.05). TFMJ had increased from a mean of 65.1 s (placebo), to 247.3 s (lower dose) and 295.5 s (higher dose, both p <  0.0001).

Levodropropizine, a common antitussive drug, suppresses seizure activity in rats with PTZ-induced status epilepticus. Given the ongoing need to find effective therapies for refractory epilepsy, the possibility of using levodropropizine as an antiepilepticshould be further explored.