Cannabinoids have been shown to have anticonvulsant properties, but no studies have evaluated the effects of cannabinoids in the hippocampal neuronal culture models of acquired epilepsy (AE) and status epilepticus (SE). This study investigated the anticonvulsant properties of the cannabinoid receptor agonist R()-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl]pyrrolol[1,2,3 de]-1,4-benzoxazinyl]-(1-naphthalenyl)methanone (WIN 55,212-2) in primary hippocampal neuronal culture models of both AE and SE. WIN 55,212-2 produced dose-dependent anticonvulsant effects against both spontaneous recurrent epileptiform discharges (SRED) (EC50 0.85 M) and SE (EC50 1.51 M), with total suppression of seizure activity at 3 M and of SE activity at 5 M. The anticonvulsant properties of WIN 55,212-2 in these preparations were...

Purpose: To describe the experience of five Israeli pediatric epilepsy clinics treating children and adolescents diagnosed as having intractable epilepsy with a regimen of medical cannabis oil. Methods: A retrospective study describing the effect of cannabidiol (CBD)-enriched medical cannabis on children with epilepsy. The cohort included 74 patients (age range 1–18 years) with intractable epilepsy resistant to >7 antiepileptic drugs. Forty-nine (66%) also failed a ketogenic diet, vagal nerve stimulator implantation, or both. They all started medical cannabis oil treatment between 2–11/2014 and were treated for at least 3 months (average 6 months). The selected formula contained CBD and tetrahydrocannabinol at a ratio of...

Conditions have been worked out for a reliable estimation of the cataleptic activity of delta'-trans-tetrahydrocannabinol (THC) after oral administration to mice, using the ring test over a period of 6 h. By this method, the activity of cannabis herb and 5 crude fractions were measured against THC; at the same time the THC contents were determined chemically. The B/C ratio (biological activity divided by chemical assay) was calculated for each. With cannabis herb the value was 3.3 and with extracts prepared with ethanol or 70% ethanol the values ranged from 3.2 to 7.1, indicating that in all samples the activity was much higher than...

In phase 1 of the study, 3 mg/kg daily of cannabidiol (CBD) was given for 30 days to 8 health human volunteers. Another 8 volunteers received the same number of identical capsules containing glucose as placebo in a double-blind setting. Neurological and physical examinations, blood and urine analysis, ECG and EEG were performed at weekly intervals. In phase 2 of the study, 15 patients suffering from secondary generalized epilepsy with temporal focus were randomly divided into two groups. Each patient received, in a double-blind procedure, 200-300 mg daily of CBD or placebo. The drugs were administered for along as 4 1/2 months. Clinical and...

Abstract Cannabidiol (CBD) reduces seizures in childhood epilepsy syndromes including Dravet syndrome (DS). A formulation of CBD has obtained orphan drug designation for these syndromes and clinical trials are currently underway. The mechanism responsible for CBD effects is not known, although it could involve targets sensitive to CBD in other neurological disorders. We believe of interest to investigate whether these potential targets are altered in DS, in particular whether the endocannabinoid system is dysregulated. To this end, lymphocytes from patients and controls were used for analysis of gene expression of transmitter receptors and transporters, ion channels, and enzymes associated with CBD effects, as well...

Cannabidiol (CBD) is the most abundant nonpsychoactive cannabinoid in cannabis. Animal studies demonstrate anticonvulsant efficacy in multiple species and models. Anecdotal reports suggest CBD to be effective in children with treatment-resistant epilepsies (TRE), especially Dravet syndrome (DS). We report results of an open label study in children with TRE in an expanded access treatment program conducted in the US under INDs. Efficacy results are reported for all patients who received at least 12 weeks of treatment (n=137). Safety results are reported for all patients who received any treatment (n=213)

The cannabinoid CB1 receptor has been shown to be the primary site of action for cannabinoid-induced effects on the central nervous system. Activation of this receptor has proven to dampen neurotransmission and produce an overall reduction in neuronal excitability. Cannabinoid compounds like D9-tetrahydrocannabinol and cannabidiol have been shown to be anticonvulsant in maximal electroshock, a model of partial seizure with secondary generalization. However, until now, it was unknown if these anticonvulsant effects are mediated by the cannabinoid CB1 receptor. Likewise, ( R)-( + )-[2,3-Dihydro-5-methyl-3- (4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone (WIN 55,212-2), a cannabimimetic compound that has been shown to decrease hyperexcitability in cell culture models via the cannabinoid...

Objective: To identify potential pharmacokinetic interactions between the pharmaceutical formulation of cannabidiol (CBD; Epidiolex) and the commonly used antiepileptic drugs (AEDs) through an open-label safety study. Serum levels were monitored to identify interactions between CBD and AEDs. Methods: In 39 adults and 42 children, CBD dose was started at 5 mg/kg/day and increased every 2 weeks by 5 mg/kg/day up to a maximum of 50 mg/kg/day. Serum AED levels were obtained at baseline prior to CBD initiation and at most study visits. AED doses were adjusted if it was determined that a clinical symptom or laboratory result was related to a potential interaction. The...

Plant-derived cannabinoids (phytocannabinoids) are compounds with emerging therapeutic potential. Early studies suggested that cannabidiol (CBD) has anticonvulsant properties in animal models and reduced seizure frequency in limited human trials. Here, we examine the antiepileptiform and antiseizure potential of CBD using in vitro electrophysiology and an in vivo animal seizure model, respectively. CBD (0.01–100 M) effects were assessed in vitro using the Mg2-free and 4-aminopyridine (4-AP) models of epileptiform activity in hippocampal brain slices via multielectrode array recordings. In the Mg2-free model, CBD decreased epileptiform local field potential (LFP) burst amplitude [in CA1 and dentate gyrus (DG) regions] and burst duration (in all regions) and...

Abstract Marijuana has been utilized as a medicinal plant to treat a variety of conditions for nearly five millennia. Over the past few years, there has been an unprecedented interest in using cannabis extracts to treat epilepsy, spurred on by a few refractory pediatric cases featured in the media that had an almost miraculous response to cannabidiol-enriched marijuana extracts. This review attempts to answer the most important questions a clinician may have regarding the use of marijuana in epilepsy. First, we review the preclinical and human evidences for the anticonvulsant properties of the different cannabinoids, mainly tetrahydrocannabinol (THC) and cannabidiol (CBD). Then, we explore...