Monoamine oxidase inhibitors (MAOIs) remain an important option for patients with treatment-resistant depression (TRD) and other psychiatric conditions, despite potentially serious drug-drug interactions and associated dietary tyramine restrictions. However, they are rarely prescribed in patients with comorbid substance use disorders (SUDs) due to concerns about potential drug interactions and limited research in these populations. This narrative review investigates the use of MAOIs in patients who use psychoactive substances, exploring potential interactions while summarizing the relatively scant literature on using MAOIs as treatments for SUDs. It synthesizes data from 219 peer-reviewed publications investigating MAOI/psychoactive substance interactions or the use of MAOIs to treat SUDs or psychiatric conditions in patients with comorbid SUDs, including 20 randomized controlled trials, 18 non-randomized interventional trials, 32 observational studies/case series, 56 case reports, 85 preclinical studies, and 8 reviews, with publication years spanning from 1955 to 2025. Data from 28 non-peer-reviewed user-submitted reports from drug use/harm reduction forums are also included. Suspected cases of serotonin toxicity have been reported for MAOIs in combination with amphetamine, dextromethorphan, 3,4-methylenedioxymethamphetamine (MDMA), meperidine (pethidine), methadone, and tramadol. Hypertensive urgency/emergency has been reported for MAOIs in combination with alcohol (varieties containing significant amounts of tyramine), amphetamine, cocaine, dextroamphetamine, khat, methamphetamine, and psilocybin mushrooms. Other notable adverse events associated with MAOIs in combination with psychoactive substances include agitation (4-bromo-2,5-dimethoxyphenethylamine [2C-B] 5-methoxy-N,N-dimethyltryptamine [5-Meo-DMT]), N,N-dimethyltryptamine [DMT]), delirium/confusion (DMT, propoxyphene, and tramadol), edema (chlordiazepoxide), intracranial hemorrhage (amphetamine, khat, and methamphetamine), mania/psychosis (DMT), rhabdomyolysis (5-MeO-DMT, DMT, and propoxyphene), and sedation/stupor/loss of consciousness (amobarbital, amphetamine, cocaine, dextroamphetamine, and propoxyphene). Fatalities have been reported for MAOIs in combination with 5-MeO-DMT, amphetamine, dextroamphetamine, dextromethorphan (in overdose), MDMA, methamphetamine, meperidine, and tramadol (in overdose). Based on our findings, some substances, such as alcoholic beverages containing significant tyramine quantities (uncommon today), amphetamines, opioids with significant serotonergic reuptake inhibition, and some hallucinogens such as the empathogen/entactogen MDMA, can pose potentially fatal risks in combination with MAOIs. However, MAOI treatment of patients who use alcoholic beverages low in tyramine, caffeine, cannabis, nicotine, sedatives, some (primarily classic) hallucinogens, and some other substances can likely be appropriately managed with careful monitoring, although psychoactive substance dose and route of administration are important safety considerations. While there was initially hope MAOIs might effectively treat some SUDs, there are no robust human data to support their efficacy in this context. Given growing levels of substance use and an increasing number of novel illicit compounds being produced, more research on MAOI safety in patients with psychiatric conditions and comorbid psychoactive substance use/misuse is essential to determining their appropriateness in this complex patient population.

Certain foods and specific drugs have been linked to epilepsy in the literature. Here, we query PubMed citations for the co-occurrence of epilepsy with foods and drugs, using a list of 217,776 molecules from the HMDB. Notably, the top associations with epilepsy include approved drugs and drug families, diagnostic markers, inducers, and vitamins. Drugs include fosphenytoin (40%), topiramate (37%), valproic acid (34%), hydantoin (20%), phenytoin (31%), carbamazepine (33%), carbamazepine-10,11-epoxide (40%), trimethadione (31%), gabapentin (14%), pregabalin (11%), flunarizine (7%), fenfluramine (4%), bumetanide (4%), KBr (18%), cannabidiol (14%), clonazepam (22%), nitrazepam (10%), diazepam (7%), lorazepam (6%), midazolam (3%), amobarbital (21%), phenobarbital (16%), flumazenil (7%) allopregnanolone (7%), pregnanolone (6%), epipregnanolone (6%), 3-hydroxypregnan-20-one (6%), and vitamin B6 (6%). Drug families and scaffolds include imidazolidine (18%), succinimide (10%), acetamide (7%), 2-pyrrolidinone (7%), pyrrolidine (6%), tetrahydropyridine (6%), and isoxazole (4%). Investigational compounds include cyano-7-nitroquinoxaline-2,3-dione (5%). Diagnostic markers include exametazime (10%) and quinolinic acid (3%). Inducers include flurothyl (37%), pentetrazol (32%), pilocarpine (25%), (+)-Bicuculline (8%), and 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP, 6%). Our analysis highlights frequently cited associations between epilepsy and specific drugs and highlights the importance of supplementing nutrients with vitamin B6 and the ketogenic diet, which increases the gamma-aminobutyric acid (GABA)/glutamate ratio. As such, our study offers dietary approaches in the treatment of this neurodegenerative disease.

As speech-related symptoms of Landau-Kleffner syndrome (LKS) are often refractory to pharmacotherapy, and resective surgery is rarely available due to the involvement of the vital cortex, multiple subpial transection (MST) was suggested to improve patient outcome and preserve cortical functions. Here, we analyze the reports about MST use in LKS, regarding its impact on seizures, language, behavior, EEG, cognition, and reported adverse effects. In conditions like LKS, surgery is not a popular treatment option and presumably should be considered sooner. Candidates for MST should be selected carefully, optimally with the unilateral onset of epileptic activity. Laterality can be assessed using a methohexital suppression test (MHXT), electrical intracarotid amobarbital test, or magnetoencephalography. After MST, a significant percentage of LKS patients present seizure-free status, normalization of EEG patterns, and rapid behavior improvement. Data comprising language outcomes are mixed, with improvement reported in 23.8-100% of cases, and no superiority was found in the only study comparing MST with a non-surgical group. Cognitive outcomes are not well described. The risk linked to MST is described as low, with cerebral edema and transient neurological deficits being the most common complications. MST successfully improves seizure, EEG, and behavioral outcomes in LKS patients. However, its beneficial impact on language and cognition is not well proven. It is generally a safe neurological operation.

Functional MRI (fMRI) is gaining importance in the preoperative assessment of language for presurgical planning. However, inconsistencies with the Wada test might arise. This current case report describes a very rare case of an epileptic patient who exhibited bilateral distribution (right > left) in the inferior frontal gyrus (laterality index [LI] = -0.433) and completely right dominance in the superior temporal gyrus (LI = -1). However, the Wada test revealed a dissociation: his motor speech was located in the left hemisphere, while he could understand vocal instructions with his right hemisphere. A clinical implication is that the LIs obtained by fMRI should be cautiously used to determine Broca's area in atypical patients; for example, even when complete right dominance is found in the temporal cortex in right-handed patients. Theoretically, as the spatially separated functions of motor speech and language comprehension (by the combined results of fMRI and Wada) can be further temporally separated (by the intracarotid amobarbital procedure) in this case report, these findings might provide direct support to Broca's initial conclusions that Broca's area is associated with acquired motor speech impairment, but not language comprehension per se. Moreover, this current finding supports the idea that once produced, motor speech can be independent from language comprehension.

Determination of language hemispheric dominance (HD) in patients undergoing evaluation for epilepsy surgery has traditionally relied on the sodium amobarbital (Wada) test. The emergence of non-invasive methods for determining language laterality has increasingly shown to be a viable alternative. In this study, we assessed the efficacy of transcranial magnetic stimulation (TMS) and magnetoencephalography (MEG), compared to the Wada test, in determining language HD in a sample of 12 patients. TMS-induced speech errors were classified as speech arrest, semantic, or performance errors, and the HD was based on the total number of errors in each hemisphere with equal weighting of all errors (classic) and with a higher weighting of speech arrests and semantic errors (weighted). Using MEG, HD for language was based on the spatial extent of long-latency activity sources localized to receptive language regions. Based on the classic and weighted language laterality index (LI) in 12 patients, TMS was concordant with the Wada in 58.33% and 66.67% of patients, respectively. In eight patients, MEG language mapping was deemed conclusive, with a concordance rate of 75% with the Wada test. Our results indicate that TMS and MEG have moderate and strong agreement, respectively, with the Wada test, suggesting they could be used as non-invasive substitutes.

The conventional intracarotid amobarbital (Wada) test has been used to assess memory function in patients being considered for temporal lobe epilepsy (TLE) surgery. Minimally invasive approaches that target the medial temporal lobe (MTL) and spare neocortex are increasingly used, but a knowledge gap remains in how to assess memory and language risk from these procedures. We retrospectively compared results of two versions of the Wada test, the intracarotid artery (ICA-Wada) and posterior cerebral artery (PCA-Wada) approaches, with respect to predicting subsequent memory and language outcomes, particularly after stereotactic laser amygdalohippocampotomy (SLAH). We included all patients being considered for SLAH who underwent both ICA-Wada and PCA-Wada at a single institution. Memory and confrontation naming assessments were conducted using standardized neuropsychological tests to assess pre- to post-surgical changes in cognitive performance. Of 13 patients who initially failed the ICA-Wada, only one patient subsequently failed the PCA-Wada (p=0.003, two-sided binomial test with p 0 =0.5) demonstrating that these tests assess different brain regions or networks. PCA-Wada had a high negative predictive value for the safety of SLAH, compared to ICA-Wada, as none of the patients who underwent SLAH after passing the PCA-Wada experienced catastrophic memory decline (0 of 9 subjects, p <.004, two-sided binomial test with p 0 =0.5), and all experienced a good cognitive outcome. In contrast, the single patient who received a left anterior temporal lobectomy after failed ICA- and passed PCA-Wada experienced a persistent, near catastrophic memory decline. On confrontation naming, few patients exhibited disturbance during the PCA-Wada. Following surgery, SLAH patients showed no naming decline, while open resection patients, whose surgeries all included ipsilateral temporal lobe neocortex, experienced significant naming difficulties (Fisher's exact test, p <.05). These findings demonstrate that (1) failing the ICA-Wada falsely predicts memory decline following SLAH, (2) PCA-Wada better predicts good memory outcomes of SLAH for MTLE, and (3) the MTL brain structures affected by both PCA-Wada and SLAH are not directly involved in language processing.