Clinically Relevant Drug Interactions with Monoamine Oxidase Inhibitors.

Monoamine oxidase inhibitors (MAOI) are a class of drugs that were originally developed for the treatment of depression but have since been expanded to be used in management of affective and neurological disorders, as well as stroke and aging-related neurocognitive changes. Ranging from irreversible to reversible and selective to non-selective, these drugs target the monoamine oxidase (MAO) enzyme and prevent the oxidative deamination of various monoamines and catecholamines such as serotonin and dopamine, respectively. Tyramine is a potent releaser of norepinephrine (NE) and is found in high concentrations in foods such as aged cheeses and meats. Under normal conditions, NE is unable to accumulate to toxic levels due to the presence of MAO-A, an enzyme that degrades neurotransmitters, including NE. When MAO-A is inhibited, the capacity to handle tyramine intake from the diet is significantly reduced causing the brain to be vulnerable to overstimulation of postsynaptic adrenergic receptors with as little as 8-10 mg of tyramine ingested and can result in life-threatening blood pressure elevations. In addition to adverse reactions with certain foods, both older and newer MAOIs can negatively interact with both sympathomimetic and serotonergic drugs. In general, patients on a MAOI want to avoid two types of medications: those that can elevate blood pressure via sympathomimetic actions (e.g., phenylephrine and oxymetazoline) and those that can increase serotonin levels via 5-HT reuptake inhibition (e.g., dextromethorphan, chlorpheniramine, and brompheniramine). Illicit drugs that stimulate the central nervous system such as ecstasy (MDMA, 3,4-methylenedioxymethamphetamine) act as serotonin releasers. Patient involvement is also crucial to ensure any interaction within the healthcare setting includes making other providers aware of a MAOI prescription as well as avoiding certain OTC medications that can interact adversely with MAOIs.

Silent Neuroleptic Malignant Syndrome: A Case Report of Atypical Antipsychotic Induced Elevation of Creatinine Kinase and Altered Mental Status.

34-year-old African American male with a diagnosis of schizophrenia was placed on aripiprazole and risperidone for psychosis and mood stabilization. Two days after medication initiation, the patient's mentation was altered and he appeared confused with an elevated creatine kinase (CK) at 7101. Medications were held and CK normalized with IV fluids. Quetiapine was initiated after medical stabilization along with lithium and paliperidone palmitate injections. After the second dose of paliperidone palmitate, the patient's mentation was altered, and repeat CK was 4272. The patient received 4 liters of IV fluid and his mental status returned to baseline. There were two case studies noted that had marked increases in serum CK with risperidone use. The first was in an adolescent who was titrated to a dose of risperidone 3mg/ day but the only abnormality was an increase in his CK levels. The next case report was in a 40-year-old female who was on risperidone 2.5mg /day for one year. She had an intention tremor, minor muscle weakness of the lower extremities with a blood pressure of 140/100 and a pulse of 100. She manifested more clinical signs of possible Neuroleptic Malignant Syndrome (NMS). This case highlights the importance of laboratory investigations when there is a high suspicion of possible NMS. It also highlights that some cases of NMS may only present as altered mental status and increased CK in which quick treatment may lead to the prevention of full-blown clinical manifestations of NMS which could be life-threatening.

Novel Designer Benzodiazepines: Comprehensive Review of Evolving Clinical and Adverse Effects.

As tranquilizers, benzodiazepines have a wide range of clinical uses. Recently, there has been a significant rise in the number of novel psychoactive substances, including designer benzodiazepines. Flubromazolam(8-bromo-6-(2-fluorophenyl)-1-methyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazeZpine) is a triazolo-analogue of flubromazepam. The most common effects noted by recreational users include heavy hypnosis and sedation, long-lasting amnesia, and rapid development of tolerance. Other effects included anxiolysis, muscle-relaxing effects, euphoria, loss of control, and severe withdrawals. Clonazolam, or 6-(2-chlorophenyl)-1-methyl-8-nitro-4H-[1,2,4]triazolo[4,3-α]-[1,4]-benzodiazepine, is a triazolo-analog of clonazepam. It is reported to be over twice as potent as alprazolam. Deschloroetizolam (2-Ethyl-9-methyl-4-phenyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine) is part of the thienodiazepine drug class, which, like benzodiazepines, stimulates GABA-A receptors. Meclonazepam ((3S)-5-(2-chlorophenyl)-3-methyl-7-nitro-1,3-dihydro-1,4-benzodiazepin-2-one) is a designer benzodiazepine with additional anti-parasitic effects. Although it has proven to be an efficacious therapy for schistosomiasis, its sedative side effects have prevented it from being marketed as a therapeutic agent. The use of DBZs has been a subject of multiple recent clinical studies, likely related to increasing presence and availability on the internet drug market and lack of regulation. Many studies have aimed to identify the prevalence of DBZs and their effects on those using them. This review discussed these designer benzodiazepines and the dangers and adverse effects that the clinician should know.

The Antisense Oligonucleotide Nusinersen for Treatment of Spinal Muscular Atrophy.

Spinal muscular atrophy (SMA) is a rare, autosomal recessive neuromuscular degenerative disease characterized by loss of spinal cord motor neurons leading to progressive muscle wasting. The most common pathology results from a homozygous disruption in the survival motor neuron 1 (SMN1) gene on chromosome 5q13 via deletion, conversion, or mutation. SMN2 is a near duplicate of SMN1 that can produce full-length SMN mRNA transcripts, but its overall production capability of these mRNA transcripts is lower than that seen in SMN1. This leads to lower levels of functional SMN protein within motor neurons. The FDA approved nusinersen in December 2016 to treat SMA associated with SMN1 gene mutation. It is administered directly to the central nervous system by intrathecal injection. An antisense oligonucleotide (ASO) drug, nusinersen, provides an upcoming and promising treatment option for SMA and represents a novel pharmacological approach with a mechanism of action relevant for other neurodegenerative disorders. Nusinersen begins with four initial loading doses that are followed by three maintenance doses per year. Three major studies (CHERISH, ENDEAR, and NURTURE) have shown to improve motor function in early and late-onset individuals and reduce the chances of ventilator requirements in pre-symptomatic infants. Studies investigating the timing of drug delivery in mouse models of SMA report the best outcomes when drugs are delivered early before any significant motor function is lost. Nusinersen is a novel therapeutic approach with consistent results in all three studies and is proof of the novel concept for treating SMA and other neurodegenerative disorders in the future.

A Comprehensive Update of the Treatment and Management of Bertolotti's Syndrome: A Best Practices Review.

Bertolotti's Syndrome is defined as chronic back pain caused by transitional lumbosacral vertebra. The transitional vertebra may present with numerous clinical manifestations leading to a myriad of associated pain types. The most common is pain in the sacroiliac joint, groin, and hip region and may or may not be associated with radiculopathy. Diagnosis is made through a combination of clinical presentations and imaging studies and falls into one of four types. The incidence of transitional vertebra has a reported incidence between 4 and 36%; however, Bertolotti's Syndrome is only diagnosed when the cause of pain is attributed to this transitional anatomy. Therefore, the actual incidence is difficult to determine. Initial management with conservative treatment includes medical management and physical therapy. Injection therapy has been established as an effective second line. Epidural steroid injection at the level of the transitional articulation is effective, with either local anesthetics alone or in combination with steroids. Surgery carries higher risks and is reserved for patients failing previous lines of treatment. Options include surgical removal of the transitional segment, decompression of stenosed foramina, and spinal fusion. Recent evidence suggests that radiofrequency ablation (RFA) around the transitional segment may also provide relief. This manuscript is a comprehensive review of the literature related to Bertolotti's Syndrome. It describes the background, including epidemiology, pathophysiology, and etiology of the Syndrome, and presents the best evidence available regarding management options. Bertolotti's Syndrome is considered an uncommon cause of chronic back pain, though the actual incidence is unclear. Most evidence supporting these therapies is of lower-level evidence with small cohorts, and more extensive studies are required to provide strong evidence supporting best practices.

Brexanolone, a GABAA Modulator, in the Treatment of Postpartum Depression in Adults: A Comprehensive Review.

Postpartum depression (PPD) is one of the three major categories on the spectrum of postpartum psychiatric syndromes. Postpartum psychiatric syndromes are classified as either postpartum blues, postpartum depression, or postpartum psychosis. Postpartum depression is important to recognize clinically because of the effect it can have on the mother-child bond. The neurosteroid allopregnanolone, a progesterone derivative, is important for its role in positively modulating GABAA receptors. GABA-mediated signaling has been previously implicated in major depressive disorder. Allopregnanolone-mediated signaling has been identified as an important therapeutic target. Treatment with an allopregnanolone-analog, brexanolone, has been shown to improve depression scores in trials for the treatment of PPD. Brexanolone is a positive allosteric modulator of GABAA and is the first drug approved by the FDA to treat postpartum depression. Brexanolone enhances the inhibitory effects of GABAA, restores dysfunctional GABAA transmembrane channels, and mimics a naturally produced progesterone metabolite that fluctuates during pregnancy and postpartum. One open-label study and two phase two studies have some significant reduction in HAM-D scores after treatment and that the effect was still there 30 days post-treatment. Per the data reported, intravenous infusion of brexanolone could be efficacious and safe for the treatment of women suffering from postpartum depression.