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cannabinoids have excellent therapeutic potential for the treatment of epilepsy. In the brain, the endocannabinoid system tends to keep neuronal activity wihtin acceptable boundaries. More importantly, cannabinoids prevent hypersynchronisation of cortical neurons (which is the very definition of a seizure). Therefore, plant cannabinoids and several terpenes can be used to boost the endocannabinoid system and help keep neuronal activity in balance as is shown by several clinical trials.

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Although preclinical data provides evidence for the therapeutic effect of several cannabinoids in epilepsy, only THC and CBD are readily available. Clinical evidence also suggests THC and CBD are therapeutic in epilepsy.

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Literature Discussion

Reducing neuronal excitability

How cannabinoids reduce neuronal excitability is not exactly known but the following options are possible:

  • Neuronal activity induces a Cl- influx through 2AG/Anandamide and CB2 (den Boon et al., 2014).
  • Anandamide reduces burst-firing in neurons (Evans et al., 2008).
  • cannabinoids reduce the number of neurotransmitter vesicles available for fusion (García-Morales et al., 2015).
  • In human neuroblastoma cells (SH-SY5Y) and mouse cortical neurons CBD and CBG both blocked sodium channels Nav1.1, 1.2 and 1.5 (Hill et al., 2014). Interestingly, CBD but not CBG protected against pentyleneterzole (PTZ)-induced seizures in rat, suggesting that the anti-convulsant effect of CBD is not just through blocking sodium channels/blocking excitability.
  • In HEK293 cells human CBD (and THC) were found to stabilize sodium channels in their inactive state. CBD was more effective at depolarized potentials thus particularly preventing over-excitation. Similar results were obtained in iPSC-neurons (Ghovanloo et al., 2018). IC50 values were:
    • hNav1.1CBD: 2.0±0.1 μM
    • hNav1.2CBD: 2.9±0.1 μM
    • hNav1.3 – CBD: 3.3±0.1 μM
    • hNav1.4 – CBD: 1.9±0.1 μM
    • hNav1.5CBD: 3.8±0.2 μM
    • hNav1.6 – CBD: 3.0±0.1 μM
    • hNav1.7 – CBD: 2.9±0.1 μM
    • hNav1.2THC: 2.4±0.1 μM
    • mNav1.6 – CBD: 2.4±0.1 μM
  • Both phytocannabinoids and endocannabinoids tend to reduce neuronal activity-dependent neurotransmitter release. This occurs both in excitatory synapses (Depolarisation-induced suppression of excitation/DSE) and inhibitory synapses (DSI). Although DSI tends to be more prominent in the brain, the combined effect of DSI and DSE often helps to suppress seizures (Alger, 2014).

Reducing neuronal synchronization

In rats, THC and other synthetic CB1 agonists, reduces synchronous firing of hippocampal principal neurons, suggesting a direct role for THC in seizure prevention (Goonawardena et al., 2011). Similarly, CB1 activation decreases synchrony in cortical neurons (Sales-Carbonell et al., 2013) suggesting THC (like substances) can be used to suppress seizures.

In healthy human volunteers, 10 mg oral THCV reduced functional network connectivity in the brain (measured by fMRI)(Rzepa et al., 2015). Although this does not prove anything in itself, it does support the idea that cannabinoids can reduce network synchronization.

In heterologous cells (HEK293), THC and CBD were found to inhibit T-type calcium channels with an IC50 of approximately 1μM (Ross et al., 2008). THC-mediated inhibition was frequency dependent where CBD-mediated inhibition was not. As T-type calcium channels function in thalamus-mediated synchronization of brain regions and are implicated in various types of epilepsy, THC and CBD are likely to suppress seizure generation.


Preclinical studies shows that, in addition to CBD, CBDV and THC also have anti-convulsant properties (Hill et al., 2013; Wallace et al., 2001).

CBD and CBG can both block NaV 1.1, 1.2 and 1.5 at micromolar concentrations. However, neither CBD nog CBG had anti-convulsant effect in PTZ-induced seizures in mice at concentrations between 50 and 200 mg/kg, suggesting sodium channel inhibition is presumably not the main anti-convulsive action of CBD (or CBG) (Hill et al., 2014).

In the rat PTZ model of epilepsy 0.25 mg/kg THCV significantly reduced seizure incidence. Similarly, prior bath application of 10 μM THCV or acute application of > 20 μM THCV prevented complex burst firing and depolarizing shifts in slice experiments (Hill et al., 2010).

In a mouse model of epilepsy (Maximal Electro Shock), the following cannabinoids were found to be anti-convulsive (effective dose/ED50)(referenced within: Devinsky et al., 2014):

  • CBD 120 mg/kg
  • Δ9THC 100 mg/kg
  • 11-OH-Δ9THC 14 mg/kg (This primary metabolite of THC is mostly produced in the liver and appears to be more effective in suppressing seizures than THC. Therefore, oral ingestion might prove to be a better route of application than sublingual application for instance, but this remains to be investigated).
  • 8β-OH-Δ9THC 100 mg/kg
  • Δ9THCA 200-400 mg/kg
  • Δ8THC 80 mg/kg
  • CBN 230 mg/kg
  • Δ9α/β-OH-hexahydro-CBN 100 mg/kg

Apart from that the doses reported above are incredibly high, it does provide a proof of principle that many cannabinoids exert anti-convulsive effects.

In another Maximal Electro Shock experiment THC was anti-convulsive at an ED50 of 42 mg/kg. This was similar to the anti-convulsive effect of CB1 agonist WIN55,212-2 (ED50 47 mg/kg) and blocked by CB1 antagonist SR141716a (AD 2.5 mg/kg) suggesting a central role for CB1. CBD was also anti-convulsive (ED50 80 mg/kg) but in a CB1 independent way (Wallace et al., 2001).

In an epilepsy model comparison the anti-epileptic effect of i.p. CBD was tested (Klein et al., 2017):

  • Acute mouse 6 Hz 44 mA: ED50 164 mg/kg
  • Acute mouse MES: ED50 83.5 mg/kg
  • Acute rat MES: ED50 88.8 mg/kg
  • Chronic mouse corneal kindling: ED50 119 mg/kg
  • Chronic rat amygdala kindling: no effect up to 300 mg/kg

Although THC/CB1 agonism is generally regarded as anti-convulsive it should be noted that in one study i.p. administration of 10 mg/kg THC or 2.5 mg/kg JWH-018 induced seizures in mice via activation of CB1 (Malyshevskaya et al., 2017).

In a comparative study, prolonged administration of THC-rich cannabis extracts caused spontaneous seizures in rats, but not dogs, suggesting inter-species differences (Whalley et al., 2018).


In the mouse PTZ model of epilepsy, 100 mg/kg β-caryophyllene increased seizure latency, suggesting an anti-epileptic effect (Oliveira et al., 2016).

In the rat PTZ model of epilepsy, 0.8 ml/kg of Cinnamosa madagascariensis essential oil completely blocked PTZ-induced convulsions (Rakotosaona et al., 2017). Linalool, limonene and myrcene are the main constituents of Cinnamosa madagascariensis essential oil and are therefore candidates for the treatment of epilepsy.

ECS involvement

As discussed above, 2AG and Anandamide can reduce neuronal excitability and drive DSI/DSE (Alger, 2014; den Boon et al., 2014; Evans et al., 2008).

In the adult PTZ model of epilepsy, extracellular accumulation of 2AG and Anandamide appeared anti-convulsive in a CB1-dependent manner. Intracellular Anandamide accumulation, however, appeared pro-convulsive in a TRPV1-dependent manner (Zareie et al., 2018).

In the rat PTZ model of epilepsy, PEA increased the latency to seizures and attenuated seizures. This effect was partially, but not entirely dependent on CB1 and CB2 receptors (Aghaei et al., 2015).

In the kainate mouse model of epilepsy, subchronic, but not acute, PEA administration reduced seizure intensity and neuronal damage (Post et al., 2018).

Audiogenic seizures in DBA/2 mice were reduced by i.p. PEA, mainly in a PPARα dependent way. CB1 agonists ACEA and WIN55,212-2 were also effective. PEA, ACEA and WIN55,212-2 also potentiated the efficacy of anti-epileptic drugs carbamazepine, diazepam, felbamate, gabapentin, phenobarbital, topiramate and valproate. In addition PEA also potentiated oxcabazepine and lamotrigine but not leviteracetam or phenytoin (Citraro et al., 2016).

In the 4-AP rat slice model of epilepsy Anandamide reuptake inhibitor AM404 and TRPV1 antagonist capsazepine suppressed seizure activity (Nazıroğlu et al., 2018).

In the rat PTZ model of epilepsy, acetaminophen/paracetamol/AM404 showed dose-dependent anti-convulsant activity which was suppressed by TRPV1 antagonists capsazepine and AMG9810 (Suemaru et al., 2018). The conflicting results of TRPV1 agonism and antagonism on seizure susceptibility suggest a complex role for TRPV1 in controlling neuronal excitability.

In mice, stimulating CB1 receptors (ACEA) or blocking TRPV1 receptors (capsazepine) protected against PTZ-induced seizures (Naderi et al., 2015). Interestingly, co-administration of both compounds attenuated the anti-convulsive effect, suggesting an interaction between CB1 and TRPV1 mediated signaling.

In the mouse pilocarpine model of epilepsy, CB1 agonist ACEA (10 mg/kg) increased the generation of new neurons where the classical anti-epileptic drug valproate did not (Andres-Mach et al., 2015, 2017). This may contribute to the anti-epileptic effect of ACEA.

In rats, the synthetic CB1 agonist WIN 55-212-2 was protective against the development of epilepsy when administered after an episode of pilocarpine-induced status epilepticus (Di Maio et al., 2014; Suleymanova et al., 2016). Sub-acute treatment with WIN 55-212-2 for 15 days dramatically reduced the frequency of spontaneous seizures, their duration and intensity and the incidence of neuronal oxidative damage.

In rats, WIN 55-212-2 delayed the onset of audiogenic epilepsy by two weeks suggesting a preventive effect of cannabinoids on the development of epilepsy as well as a curative effect (Vinogradova and van Rijn, 2015).

In P10 rat pups, CB1 agonism (ACEA) and CB1/2 agonism (WIN55,212-2) were anti-convulsant. CB1 and CB2 antagonism were pro-convulsant, while GPR55 agonism was ineffective. Unlike P10 pups and adults, CB1 agonism was ineffective in P20 pups suggesting variable efficacy of CB1 agonism in different stages of life (Huizenga et al., 2017).

In the rat PTZ and Maximal Electro Shock models of epilepsy CB1 agonist ACEA was anti-convulsant. Co-administration of BK channel antagonist paxilline attenuated the anti-convulsant effect of ACEA suggesting the involvement of BK channels in the action mechanism of ACEA (Asaadi et al., 2017).

In rats that were chronically treated with CP 55,940 (CB1/2 full agonist, GPR55 antagonist) during adolescence, PTZ-induced seizures in adulthood showed higher lethality suggesting a maladaptive effect of adolescent cannabinoid intake (Spring et al., 2015).

In the mouse maximal electroshock seizure threshold model of epilepsy various combinations of Anandamide reuptake inhibitors, FAAH inhibitors, CB1 and TRPV1 agonists showed anticonvulsant effects (Tutka et al., 2017). In descending order:

In a mouse electroshock model of epilepsy 5 mg/kg WIN55,212-2 significantly potentiated the anti-convulsant effect of gabapentin and leviteracetam but not lacosamide, oxcabarzepine, pregabalin or tiagabine (Florek-Luszczki et al., 2014, 2015).

In a guinea pig kainate model of epilepsy AM404 (TRPV1 agonist and endocannabinoid reuptake inhibitor) and URB597 (FAAH inhibitor) were anti-convulsive whereas AM251 (CB1 antagonist) was not (Shubina et al., 2015). Inhibiting endocannabinoid reuptake or degradation also prevented hippocampal circuit remodeling normally seen during epileptogenesis (Shubina et al., 2017).

In mice FAAH inhibitor URB597 and CB1 agonist ACEA reduced cocaine-induced seizures whereas CB1 antagonist AM251 prevented this anti-epileptic effect (Vilela et al., 2015).

Interestingly, in a rat traumatic brain injury model CB1 antagonist SR141716a prevented long-term hyperexcitability, which is at least apparently at odds with a protective effect of CB1 agonism in the development of epilepsy (Wang et al., 2016).

In HEK293T cells, several epilepsy-associated sodium channel mutants were analysed (Nav1.1 arg1648his and asn1788lys and Nav1.6 asn1768asp and leu1331val). The Nav1.6, but not Nav1.1 mutants, showed increased resurgent sodium currents, which may increase neuronal excitability and thus cause the epileptic phenotype. CBD was found to specifically reduce resurgent sodium currents and action potential firing which may help explain the anti-epileptic effect of CBD (Patel et al., 2016).

In lymphocytes from Dravet syndrome patients, CBD targets within the ECS were analyzed. The voltage-dependent calcium channel alpha1h (Cav3.2) and CB2 were up-regulated (Rubio et al., 2016), suggesting their involvement in the disease or the bodies’ adaptive response to the disease.

In Xenopus oocytes expressing recombinant human GABAA receptors the effect of CBD and 2AG was tested (Bakas et al., 2017). 2AG and CBD:

  • were positive allosteric modulators at α1-6βγ2 receptors
  • enhanced GABAergic current 4-fold at α2-containing receptors
  • enhanced GABAergic current at concentrations ranging from 0.01 to 1 μM at α4β2δ receptors

In the mouse PTZ model of epilepsy 60 mg/kg CBD attenuated seizures. This attenuation was prevented by CB1, CB2 and TRPV1 antagonists suggesting the anti-epileptic effect has complex pharmacology (Vilela et al., 2017).

In patients with Dravet syndrome (SCN1A/Nav1.1 mutations) additional CACNA1A/Cav2.1 mutations produced more seizures, earlier onset of seizures and more prolonged seizures, suggesting a role for Cav2.1 in seizure development (Ohmori et al., 2013).

In a genetic mouse model of Dravet syndrome, CBD was found to decrease the duration and severity of spontaneous and thermally generated seizures and improve autistic-like social behavior. This effect was associated with restoration of interneuron excitability and was occluded by a GPR55 antagonist suggesting a beneficial CBD-GPR55 interaction (Kaplan et al., 2017).

In the rat kainate model of temporal lobe epilepsy 100 mg/kg (in vivo) or 10 μM (slices) CBD restored normal hippocampal interneuron excitability and prevented PV and CCK positive interneuron death (Khan et al., 2018).

In mice lacking DAGL/2AG production kainate-induced seizures were much more severe. The seizure suppressing effect appeared to depend on CB1 and presumably CB2 (Sugaya et al., 2016).

In the mouse pilocarpine model of epilepsy, 30 mg/kg CBD restored non-NMDA LTP. This effect was at least partially mediated by 5-HT1A receptors (Maggio et al., 2018).

In the rat pilocarpine model of epilepsy, status epilepticus strengthens GABAergic drive between interneurons. This strengthening can be inhibited via CB1 signalling (Yu et al., 2016).

Low frequency stimulation is known to have an anti-epileptic effect in experimental epilepsy models such as kindling. Kindling reduces CB1 expression in the brain wherease low frequency stimulation increases CB1 expression. Blocking CB1 receptors abolishes the effect of low frequency stimulation in kindling, suggesting an anti-epileptic effect of CB1 during low frequency stimulation (Mardani et al., 2018).

In mice with diazepam-resistent status epilepticus, inhibition of MAGL/2AG degradation reduced the duration of status epilepticus by 47%. In mice fed a ketogenic diet, MAGL inhibition immediately abolished seizures (Terrone et al., 2017).

In the rat PTZ model of epilepsy CB2 agonist AM1241 exacerbated seizures while CB2 antagonist AM630 was anti-convulsant (de Carvalho et al., 2016).


Aghaei, I., Rostampour, M., Shabani, M., Naderi, N., Motamedi, F., Babaei, P., and Khakpour-Taleghani, B. (2015). Palmitoylethanolamide attenuates PTZ-induced seizures through CB1 and CB2 receptors. epilepsy Res. 117, 23–28.

Alger, B.E. (2014). Seizing an opportunity for the endocannabinoid system. epilepsy Curr. Am. epilepsy Soc. 14, 272–276.

Andres-Mach, M., Haratym-Maj, A., Zagaja, M., Rola, R., Maj, M., Chrościńska-Krawczyk, M., and Luszczki, J.J. (2015). ACEA (a highly selective cannabinoid CB1 receptor agonist) stimulates hippocampal neurogenesis in mice treated with antiepileptic drugs. Brain Res.

Andres-Mach, M., Zagaja, M., Haratym-Maj, A., Rola, R., Maj, M., Haratym, J., Dudra-Jastrzębska, M., and Łuszczki, J.J. (2017). A Long-Term Treatment with Arachidonyl-2’-Chloroethylamide Combined with Valproate Increases Neurogenesis in a Mouse Pilocarpine Model of epilepsy. Int. J. Mol. Sci. 18.

Asaadi, S., Jahanbakhshi, M., Lotfinia, M., and Naderi, N. (2017). The Role of BK Channels in Antiseizure Action of the CB1 Receptor Agonist ACEA in Maximal Electroshock and Pentylenetetrazole Models of Seizure in Mice. Iran. J. Pharm. Res. IJPR 16, 640–647.

Bakas, T., van Nieuwenhuijzen, P.S., Devenish, S.O., McGregor, I.S., Arnold, J.C., and Chebib, M. (2017). The direct actions of cannabidiol and 2-arachidonoyl glycerol at GABAA receptors. Pharmacol. Res. 119, 358–370.

den Boon, F.S., Chameau, P., Houthuijs, K., Bolijn, S., Mastrangelo, N., Kruse, C.G., Maccarrone, M., Wadman, W.J., and Werkman, T.R. (2014). endocannabinoids produced upon action potential firing evoke a Cl(-) current via type-2 cannabinoid receptors in the medial prefrontal cortex. Pflüg. Arch. Eur. J. Physiol. 466, 2257–2268.

de Carvalho, C.R., Hoeller, A.A., Franco, P.L.C., Martini, A.P.S., Soares, F.M.S., Lin, K., Prediger, R.D., Whalley, B.J., and Walz, R. (2016). The cannabinoid CB2 receptor-specific agonist AM1241 increases pentylenetetrazole-induced seizure severity in Wistar rats. epilepsy Res. 127, 160–167.

Citraro, R., Russo, E., Leo, A., Russo, R., Avagliano, C., Navarra, M., Calignano, A., and De Sarro, G. (2016). Pharmacokinetic-pharmacodynamic influence of N-palmitoylethanolamine, arachidonyl-2’-chloroethylamide and WIN 55,212-2 on the anticonvulsant activity of antiepileptic drugs against audiogenic seizures in DBA/2 mice. Eur. J. Pharmacol. 791, 523–534.

Devinsky, O., Cilio, M.R., Cross, H., Fernandez-Ruiz, J., French, J., Hill, C., Katz, R., Di Marzo, V., Jutras-Aswad, D., Notcutt, W.G., et al. (2014). Cannabidiol: pharmacology and potential therapeutic role in epilepsy and other neuropsychiatric disorders. Epilepsia 55, 791–802.

Di Maio, R., Cannon, J.R., and Timothy Greenamyre, J. (2014). Post-status epilepticus treatment with the cannabinoid agonist WIN 55,212-2 prevents chronic epileptic hippocampal damage in rats. Neurobiol. Dis. 73C, 356–365.

Evans, R.M., Wease, K.N., MacDonald, C.J., Khairy, H.A., Ross, R.A., and Scott, R.H. (2008). Modulation of sensory neuron potassium conductances by Anandamide indicates roles for metabolites. Br. J. Pharmacol. 154, 480–492.

Florek-Luszczki, M., Zagaja, M., and Luszczki, J.J. (2014). Influence of WIN 55,212-2 on the anticonvulsant and acute neurotoxic potential of clobazam and lacosamide in the maximal electroshock-induced seizure model and chimney test in mice. epilepsy Res. 108, 1728–1733.

Florek-Luszczki, M., Wlaz, A., Zagaja, M., Andres-Mach, M., Kondrat-Wrobel, M.W., and Luszczki, J.J. (2015). Effects of WIN 55,212-2 (a synthetic cannabinoid CB1 and CB2 receptor agonist) on the anticonvulsant activity of various novel antiepileptic drugs against 6Hz-induced psychomotor seizures in mice. Pharmacol. Biochem. Behav.

García-Morales, V., Montero, F., and Moreno-López, B. (2015). cannabinoid agonists rearrange synaptic vesicles at excitatory synapses and depress motoneuron activity in vivo. Neuropharmacology.

Ghovanloo, M.-R., Shuart, N.G., Mezeyova, J., Dean, R.A., Ruben, P.C., and Goodchild, S.J. (2018). Inhibitory effects of cannabidiol on voltage-dependent sodium currents. J. Biol. Chem.

Goonawardena, A.V., Riedel, G., and Hampson, R.E. (2011). cannabinoids alter spontaneous firing, bursting, and cell synchrony of hippocampal principal cells. Hippocampus 21, 520–531.

Hill, A.J., Weston, S.E., Jones, N.A., Smith, I., Bevan, S.A., Williamson, E.M., Stephens, G.J., Williams, C.M., and Whalley, B.J. (2010). Δ9-Tetrahydrocannabivarin suppresses in vitro epileptiform and in vivo seizure activity in adult rats: Anticonvulsant Potential of Δ9-THCV. Epilepsia 51, 1522–1532.

Hill, A.J., Jones, N.A., Smith, I., Hill, C.L., Williams, C.M., Stephens, G.J., and Whalley, B.J. (2014). Voltage-gated sodium (NaV) channel blockade by plant cannabinoids does not confer anticonvulsant effects per se. Neurosci. Lett. 566, 269–274.

Hill, T.D.M., Cascio, M.-G., Romano, B., Duncan, M., Pertwee, R.G., Williams, C.M., Whalley, B.J., and Hill, A.J. (2013). Cannabidivarin-rich cannabis extracts are anticonvulsant in mouse and rat via a CB1 receptor-independent mechanism. Br. J. Pharmacol. 170, 679–692.

Huizenga, M.N., Wicker, E., Beck, V.C., and Forcelli, P.A. (2017). Anticonvulsant effect of cannabinoid receptor agonists in models of seizures in developing rats. Epilepsia.

Kaplan, J.S., Stella, N., Catterall, W.A., and Westenbroek, R.E. (2017). Cannabidiol attenuates seizures and social deficits in a mouse model of Dravet syndrome. Proc. Natl. Acad. Sci. U. S. A. 114, 11229–11234.

Khan, A.A., Shekh-Ahmad, T., Khalil, A., Walker, M.C., and Ali, A.B. (2018). Cannabidiol exerts antiepileptic effects by restoring hippocampal interneuron functions in a temporal lobe epilepsy model. Br. J. Pharmacol. 175, 2097–2115.

Klein, B.D., Jacobson, C.A., Metcalf, C.S., Smith, M.D., Wilcox, K.S., Hampson, A.J., and Kehne, J.H. (2017). Evaluation of Cannabidiol in Animal Seizure Models by the epilepsy Therapy Screening Program (ETSP). Neurochem. Res.

Maggio, N., Shavit Stein, E., and Segal, M. (2018). Cannabidiol Regulates Long Term Potentiation Following Status Epilepticus: Mediation by Calcium Stores and Serotonin. Front. Mol. Neurosci. 11, 32.

Malyshevskaya, O., Aritake, K., Kaushik, M.K., Uchiyama, N., Cherasse, Y., Kikura-Hanajiri, R., and Urade, Y. (2017). Natural (∆(9)-THC) and synthetic (JWH-018) cannabinoids induce seizures by acting through the cannabinoid CB1 receptor. Sci. Rep. 7, 10516.

Mardani, P., Oryan, S., Sarihi, A., Alaei, E., Komaki, A., and Mirnajafi-Zadeh, J. (2018). endocannabinoid CB1 receptors are involved in antiepileptogenic effect of low frequency electrical stimulation during perforant path kindling in rats. epilepsy Res. 144, 71–81.

Naderi, N., Shafieirad, E., Lakpoor, D., Rahimi, A., and Mousavi, Z. (2015). Interaction between cannabinoid Compounds and Capsazepine in Protection against Acute Pentylenetetrazole-induced Seizure in Mice. Iran. J. Pharm. Res. IJPR 14, 115–120.

Nazıroğlu, M., Taner, A.N., Balbay, E., and Çiğ, B. (2018). Inhibitions of Anandamide transport and FAAH synthesis decrease apoptosis and oxidative stress through inhibition of TRPV1 channel in an in vitro seizure model. Mol. Cell. Biochem.

Ohmori, I., Ouchida, M., Kobayashi, K., Jitsumori, Y., Mori, A., Michiue, H., Nishiki, T., Ohtsuka, Y., and Matsui, H. (2013). CACNA1A variants may modify the epileptic phenotype of Dravet syndrome. Neurobiol. Dis. 50, 209–217.

Oliveira, C.C. de, Oliveira, C.V. de, Grigoletto, J., Ribeiro, L.R., Funck, V.R., Grauncke, A.C.B., Souza, T.L. de, Souto, N.S., Furian, A.F., Menezes, I.R.A., et al. (2016). Anticonvulsant activity of β-caryophyllene against pentylenetetrazol-induced seizures. epilepsy Behav. EB 56, 26–31.

Patel, R.R., Barbosa, C., Brustovetsky, T., Brustovetsky, N., and Cummins, T.R. (2016). Aberrant epilepsy-associated mutant Nav1.6 sodium channel activity can be targeted with cannabidiol. Brain J. Neurol.

Post, J.M., Loch, S., Lerner, R., Remmers, F., Lomazzo, E., Lutz, B., and Bindila, L. (2018). Antiepileptogenic Effect of Subchronic Palmitoylethanolamide Treatment in a Mouse Model of Acute epilepsy. Front. Mol. Neurosci. 11, 67.

Rakotosaona, R., Randrianarivo, E., Rasoanaivo, P., Nicoletti, M., Benelli, G., and Maggi, F. (2017). Effect of the Leaf Essential Oil from Cinnamosma madagascariensis Danguy on Pentylenetetrazol-induced Seizure in Rats. Chem. Biodivers.

Ross, H.R., Napier, I., and Connor, M. (2008). Inhibition of recombinant human T-type calcium channels by Delta9-tetrahydrocannabinol and cannabidiol. J. Biol. Chem. 283, 16124–16134.

Rubio, M., Valdeolivas, S., Piscitelli, F., Verde, R., Satta, V., Barroso, E., Montolio, M., Aras, L.M., Di Marzo, V., Sagredo, O., et al. (2016). Analysis of endocannabinoid signaling elements and related proteins in lymphocytes of patients with Dravet syndrome. Pharmacol. Res. Perspect. 4, e00220.

Rzepa, E., Tudge, L., and McCabe, C. (2015). The CB1 Neutral Antagonist Tetrahydrocannabivarin Reduces Default Mode Network and Increases Executive Control Network Resting State Functional Connectivity in Healthy Volunteers. Int. J. Neuropsychopharmacol. Off. Sci. J. Coll. Int. Neuropsychopharmacol. CINP.

Sales-Carbonell, C., Rueda-Orozco, P.E., Soria-Gómez, E., Buzsáki, G., Marsicano, G., and Robbe, D. (2013). Striatal GABAergic and cortical glutamatergic neurons mediate contrasting effects of cannabinoids on cortical network synchrony. Proc. Natl. Acad. Sci. U. S. A. 110, 719–724.

Shubina, L., Aliev, R., and Kitchigina, V. (2015). Attenuation of kainic acid-induced status epilepticus by inhibition of endocannabinoid transport and degradation in guinea pigs. epilepsy Res. 111, 33–44.

Shubina, L., Aliev, R., and Kitchigina, V. (2017). endocannabinoid-dependent protection against kainic acid-induced long-term alteration of brain oscillations in guinea pigs. Brain Res. 1661, 1–14.

Spring, M.G., Schoolcraft, K.D., and López, H.H. (2015). The effects of adolescent cannabinoid exposure on seizure susceptibility and lethality in adult male rats. Neurotoxicol. Teratol.

Suemaru, K., Yoshikawa, M., Aso, H., and Watanabe, M. (2018). TRPV1 mediates the anticonvulsant effects of acetaminophen in mice. epilepsy Res. 145, 153–159.

Sugaya, Y., Yamazaki, M., Uchigashima, M., Kobayashi, K., Watanabe, M., Sakimura, K., and Kano, M. (2016). Crucial Roles of the endocannabinoid 2-Arachidonoylglycerol in the Suppression of Epileptic Seizures. Cell Rep.

Suleymanova, E.M., Shangaraeva, V.A., van Rijn, C.M., and Vinogradova, L.V. (2016). The cannabinoid receptor agonist WIN55.212 reduces consequences of status epilepticus in rats. Neuroscience.

Terrone, G., Pauletti, A., Salamone, A., Rizzi, M., Villa, B.R., Porcu, L., Sheehan, M.J., Guilmette, E., Butler, C.R., Piro, J.R., et al. (2017). Inhibition of monoacylglycerol lipase terminates diazepam-resistant status epilepticus in mice and its effects are potentiated by a ketogenic diet. Epilepsia.

Tutka, P., Wlaź, A., Florek-Łuszczki, M., Kołodziejczyk, P., Bartusik-Aebisher, D., and Łuszczki, J.J. (2017). Arvanil, olvanil, AM 1172 and LY 2183240 (various cannabinoid CB1 receptor agonists) increase the threshold for maximal electroshock-induced seizures in mice. Pharmacol. Rep. PR 70, 106–109.

Vilela, L.R., Gobira, P.H., Viana, T.G., Medeiros, D.C., Ferreira-Vieira, T.H., Doria, J.G., Rodrigues, F., Aguiar, D.C., Pereira, G.S., Massessini, A.R., et al. (2015). Enhancement of endocannabinoid signaling protects against cocaine-induced neurotoxicity. Toxicol. Appl. Pharmacol.

Vilela, L.R., Lima, I.V., Kunsch, É.B., Pinto, H.P.P., de Miranda, A.S., Vieira, É.L.M., de Oliveira, A.C.P., Moraes, M.F.D., Teixeira, A.L., and Moreira, F.A. (2017). Anticonvulsant effect of cannabidiol in the pentylenetetrazole model: Pharmacological mechanisms, electroencephalographic profile, and brain cytokine levels. epilepsy Behav. EB 75, 29–35.

Vinogradova, L.V., and van Rijn, C.M. (2015). Long-term disease-modifying effect of the endocannabinoid agonist WIN55,212-2 in a rat model of audiogenic epilepsy. Pharmacol. Rep. PR 67, 501–503.

Wallace, M.J., Wiley, J.L., Martin, B.R., and DeLorenzo, R.J. (2001). Assessment of the role of CB1 receptors in cannabinoid anticonvulsant effects. Eur. J. Pharmacol. 428, 51–57.

Wang, X., Wang, Y., Zhang, C., Liu, C., Zhao, B., Wei, N., Zhang, J.-G., and Zhang, K. (2016). CB1 Receptor Antagonism Prevents Long-Term Hyperexcitability after Head Injury by Regulation of Dynorphin-KOR System and mGluR5 in Rat Hippocampus. Brain Res.

Whalley, B.J., Lin, H., Bell, L., Hill, T., Patel, A., Gray, R.A., Elizabeth Roberts, C., Devinsky, O., Bazelot, M., Williams, C.M., et al. (2018). Species-specific susceptibility to cannabis-induced convulsions. Br. J. Pharmacol.

Yu, J., Swietek, B., Proddutur, A., and Santhakumar, V. (2016). Dentate cannabinoid-sensitive interneurons undergo unique and selective strengthening of mutual synaptic inhibition in experimental epilepsy. Neurobiol. Dis. 89, 23–35.

Zareie, P., Sadegh, M., Palizvan, M.R., and Moradi-Chameh, H. (2018). Anticonvulsive effects of endocannabinoids; an investigation to determine the role of regulatory components of endocannabinoid metabolism in the Pentylenetetrazol induced tonic- clonic seizures. Metab. Brain Dis.

Clinical Trials

THC / cannabis:

In 1949, the anti-convulsant activity of THC was tested on 5 children with severe grand mal epilepsy. In 3 children, THC was equally effective as previously tried therapies, in one child seizures were almost completely prevented and in the last one all seizures were stopped (Davis and Ramsey, 1949).

In one patient with idiopathic generalized epilepsy the effect of smoked cannabis sativa and cannabis indica was tested using EEG recordings. The results indicate that cannabis use reduces both interictal and ictal events warranting larger scale trials (Sivakumar et al., 2017). The study also showed a stronger effect for indica cannabis over indica/sativa mixtures. More studies are required.

Interestingly, an observational study showed that recent cannabis use may actually prevent the development of seizures/epilepsy (Brust et al., 1992), suggesting a prophylactic effect of cannabinoids.

In a survey of Australian families using illicit ‘street’ cannabis oil to treat their children with drug-resistant epilepsy, cannabis oil was perceived to be effective with:

·       51% reporting 75-100% seizure reduction

·       10% reporting a 50-75% seizure reduction

·       0% reporting a 25-50% seizure reduction

·       4% reporting a 0-25% seizure reduction

·       20% reporting no change in seizure frequency

·       8% reporting an increase in seizure frequency

Interestingly, although most families expected the oil to be CBD-dominant, most samples actually contained THC or were even THC-dominant. The perceived efficacy of the oil did not correlate with the presence or absence of THC. Oils that were perceived to be effective contained more β-caryophyllene than oils deemed ineffective, although the average amount of β-caryophyllene of 50 μg/kg/day is not expected to be anti-convulsant in itself (Suraev et al., 2018).


In a double-blind, placebo-controlled, multi-center trial the effect of CBD on drop seizures was measured in 225 Lennox-Gastaut syndrome patients. Average seizure frequency was 85/day before treatment. Patients on placebo showed a reduction of 17.2% in seizure frequency. Patients receiving 20 mg/kg CBD showed a 41.9% reduction in seizure frequency (p=0.005 compared to placebo). Patients receiving 10 mg/kg CBD showed a 37.2% reduction in seizure frequency (p=0.002 compared to placebo). 9% of the patients receiving CBD showed increased liver aminotransferase levels. Other reported adverse effects were somnolence, decreased appetite and diarrhea (Devinsky et al., 2018).

In a similar study with 171 Lennox-Gastaut patients, 20 mg/kg/day CBD for 14 weeks reduced drop seizure frequency by 43.9% compared to 21.8% for placebo. Mild adverse effects (diarrhea, somnolence, pyrexia, reduced appetite and vomiting) occurred for 86% of the CBD group compared to 69% of the placebo group (Thiele et al., 2018).

In a double-blind, placebo-controlled trial with 120 children/young adults with Dravet syndrome, 20 mg/kg/day CBD was compared with placebo. CBD produced at least 50% seizure reduction in 43% of patients compared to 27% with placebo. There was no significant change in non-convulsive seizures. The patient’s overall condition improved in 62% of the CBD group compared to 34% of the placebo group. Adverse events (diarrhea, vomiting, fatigue, pyrexia, somnolence and abnormal liver enzyme values) were more frequent in the CBD group, but did not lead to increased withdrawals (Devinsky et al., 2017).

Two clinical trials in the 1980’s investigated the therapeutic properties of CBD in epilepsy. CBD was found to be effective in 50% of patients, meaning that seizure occurrence was reduced by >50%. The occurrence of seizures was reduced by less than 50% in a further 37.5% with no effect observed in the remaining 12.5% (Cunha et al., 1980; Pickering et al., 2011).

In a trial of 15 patients with refractory secondary generalized epilepsy 8 patients received 200-300 mg CBD/day for up to 4.5 months and 7 patients received placebo. 7 out of 8 patients receiving CBD showed improvement compared to only 1 of 7 patients receiving placebo (Carlini and Cunha, 1981).

Apart from seizure reduction, CBD was reported to significantly improve Quality Of Life in children with epilepsy (Rosenberg et al., 2017).

In one very public case, a girl with Dravet syndrome (loss of function mutation in the sodium channel SCN1A), went from having more than 50 convulsive seizures per day to less than 3 nocturnal seizures per month by using extract from a Cannabis variety Charlotte’s Web, which has a THC content of 0.5% and a CBD content of 17% (Maa and Figi, 2014). The authors stress that there is synergy between cannabinoids and that cannabis extracts are superior to individually purified cannabinoids.

A meta-analysis of studies investigating the effect of CBD in treatment-resistant epilepsy found that 20 mg/kg CBD was more effective than placebo in reducing seizure frequency by more than 50%. Pooled data suggests that 55.8% report improved quality of life, 48.5% of patients experience >50% reduction of seizures and 8.5% experience complete seizure freedom (Stockings et al., 2018).

CBD was tested in five patients with Sturge-Weber syndrome with treatment-resistant epilepsy. After 8 weeks of CBD, two out of five patients reported a >50% seizure reduction and improved quality of life, suggesting a positive effect of CBD treatment (Kaplan et al., 2017).

In a dose-escalation study from 5 to 50 mg/kg/day, CBD dose-dependently increased serum levels of topiramate, rufinamide and N-desmethylclobazam and increased levels of clobazam. In adults, also increased serum levels of zonisamide and eslicabazepine. Apart from N-desmethylclobazam and clobazam, all serum levels remained within the therapeutic range. Patients on CBD and valproate also had significantly increased AST/ALT levels (Gaston et al., 2017).


In one case report of a refractory epilepsy patient, self medication with a CBDV-rich extract dramatically improved clinical symptoms. Further experiments on human brain slices suggests CBDV may prevent GABAA receptor rundown (Morano et al., 2016).

Other cannabinoids (such as THCV) are likely to have therapeutic effects as well but this has not yet been investigated.


Brust, J.C., Ng, S.K., Hauser, A.W., and Susser, M. (1992). Marijuana use and the risk of new onset seizures. Trans. Am. Clin. Climatol. Assoc. 103, 176–181.

Carlini, E.A., and Cunha, J.M. (1981). Hypnotic and antiepileptic effects of cannabidiol. J. Clin. Pharmacol. 21, 417S-427S.

Cunha, J.M., Carlini, E.A., Pereira, A.E., Ramos, O.L., Pimentel, C., Gagliardi, R., Sanvito, W.L., Lander, N., and Mechoulam, R. (1980). Chronic administration of cannabidiol to healthy volunteers and epileptic patients. Pharmacology 21, 175–185.

Devinsky, O., Cross, J.H., Laux, L., Marsh, E., Miller, I., Nabbout, R., Scheffer, I.E., Thiele, E.A., Wright, S., and Cannabidiol in Dravet Syndrome Study Group (2017). Trial of Cannabidiol for Drug-Resistant Seizures in the Dravet Syndrome. N. Engl. J. Med. 376, 2011–2020.

Devinsky, O., Patel, A.D., Cross, J.H., Villanueva, V., Wirrell, E.C., Privitera, M., Greenwood, S.M., Roberts, C., Checketts, D., VanLandingham, K.E., et al. (2018). Effect of Cannabidiol on Drop Seizures in the Lennox-Gastaut Syndrome. N. Engl. J. Med. 378, 1888–1897.

Gaston, T.E., Bebin, E.M., Cutter, G.R., Liu, Y., Szaflarski, J.P., and UAB CBD Program (2017). Interactions between cannabidiol and commonly used antiepileptic drugs. Epilepsia 58, 1586–1592.

Kaplan, E.H., Offermann, E.A., Sievers, J.W., and Comi, A.M. (2017). Cannabidiol Treatment for Refractory Seizures in Sturge-Weber Syndrome. Pediatr. Neurol.

Maa, E., and Figi, P. (2014). The case for medical marijuana in epilepsy. Epilepsia 55, 783–786.

Morano, A., Cifelli, P., Nencini, P., Antonilli, L., Fattouch, J., Ruffolo, G., Roseti, C., Aronica, E., Limatola, C., Di Bonaventura, C., et al. (2016). Cannabis in epilepsy: From clinical practice to basic research focusing on the possible role of cannabidivarin. Epilepsia Open 1, 145–151.

Pickering, E.E., Semple, S.J., Nazir, M.S., Murphy, K., Snow, T.M., Cummin, A.R., Moosavi, S.H., Guz, A., and Holdcroft, A. (2011). cannabinoid effects on ventilation and breathlessness: a pilot study of efficacy and safety. Chron. Respir. Dis. 8, 109–118.

Rosenberg, E.C., Louik, J., Conway, E., Devinsky, O., and Friedman, D. (2017). Quality of Life in Childhood epilepsy in pediatric patients enrolled in a prospective, open-label clinical study with cannabidiol. Epilepsia 58, e96–e100.

Sivakumar, S., Zutshi, D., Seraji-Bozorgzad, N., and Shah, A.K. (2017). Effects of Marijuana on Ictal and Interictal EEG Activities in Idiopathic Generalized epilepsy. J. Clin. Neurophysiol. Off. Publ. Am. Electroencephalogr. Soc. 34, e1–e4.

Stockings, E., Zagic, D., Campbell, G., Weier, M., Hall, W.D., Nielsen, S., Herkes, G.K., Farrell, M., and Degenhardt, L. (2018). Evidence for cannabis and cannabinoids for epilepsy: a systematic review of controlled and observational evidence. J. Neurol. Neurosurg. Psychiatry.

Suraev, A., Lintzeris, N., Stuart, J., Kevin, R.C., Blackburn, R., Richards, E., Arnold, J.C., Ireland, C., Todd, L., Allsop, D.J., et al. (2018). Composition and Use of Cannabis Extracts for Childhood epilepsy in the Australian Community. Sci. Rep. 8, 10154.

Thiele, E.A., Marsh, E.D., French, J.A., Mazurkiewicz-Beldzinska, M., Benbadis, S.R., Joshi, C., Lyons, P.D., Taylor, A., Roberts, C., Sommerville, K., et al. (2018). Cannabidiol in patients with seizures associated with Lennox-Gastaut syndrome (GWPCARE4): a randomised, double-blind, placebo-controlled phase 3 trial. Lancet Lond. Engl. 391, 1085–1096.