Herbal Medicine in Mexico: A Cause of Hepatotoxicity. A Critical Review.

In Mexico, herbal products are commonly used as therapeutic tools. The analysis of several publications reveals that there are dozens of different herbs and herbal products used for different reasons, some of which have been implicated in causing toxic liver disease. However, methodological aspects limit the attribution of causality, and the precise incidence and clinical manifestations of herb-induced liver injury have not been well characterized. This review outlines the history of traditional herbal medicine in Mexico, critically summarizes the mechanisms and adverse effects of commonly used herbal plants, and examines the regulatory issues regarding the legal use of these products.

Prevalence of hepatitis C virus infection among patients undergoing haemodialysis in Latin America.

Hepatitis C infection is a worldwide problem. The global prevalence of the hepatitis C virus (HCV) averages 3%. Moreover, its prevalence among patients undergoing haemodialysis (HD) varies worldwide, ranging from as low as 1% to up to 70%. There are few data on its prevalence in developing countries, and even less information is available on HD patients. A literature review revealed that the prevalence of HCV infection among patients undergoing HD in Latin America ranges from 4.2 to 83.9%, with most data stemming from Argentina, Brazil, Mexico, Peru, Chile, Venezuela and Cuba. The most common genotype was genotype 1, and subtype 1b was the most frequent. The risk factors associated with this condition were the duration of the HD treatment and blood transfusion before hepatitis C screening. In addition, HCV RNA detection by polymerase chain reaction is crucial for the diagnosis of HCV infection in HD patients. Trials using combinations of new oral antiviral drugs, such as sofosbuvir and combo (ombitasvir, paritaprevir, ritonavir and dasabuvir), should be the next step in the improvement of care among HD patients with HCV, because these therapeutic agents apparently do not require dose adjustment according to renal function. Finally, information on this subgroup of patients remains unavailable in some countries; therefore, additional studies are needed to determine the prevalence trend of HCV infection in these populations.

Alternativas de analgesia: interacciones entre fármacos y receptores / Analgesic alternatives: interactions between drugs and receptors

No obstante los adelantos en el conocimiento y tratamiento del dolor agudo y del dolor crónico, esta entidad continúa siendo un azote para la humanidad. Se ha considerado que más de 1’500,000’000,000 de seres humanos sufren de dolor crónicomoderado a severo, lo que significa un elevado costo económico y de salud, aun en los países más desarrollados. Por siglos la humanidad ha utilizado remedios para aliviar este sufrimiento y aunque el uso de opioides y de analgésicos antiinflamatoriosno esteroideos transformó el manejo racional del dolor, sus efectos secundarios son una restricción que limita su uso y eficacia terapéutica. El conocimiento de novedosos nociceptores y de sus ligandos revolucionó el conocimiento del dolor, facilitando tanto su prevención como su tratamiento. El uso de fármacos con acción analgésica en diversos receptores específicos de las múltiples y complejas vías dolorosas se fundamenta en el conocimiento de los mecanismos de interacción molecular involucrados en diversos nociceptores como por ejemplo los canales de sodio y potasio, los receptores purinérgicos, los receptores NMDA, los receptorescannabinoides, entre otros muchos. El redescubrimiento de las características analgésicas de antiguos fármacos y el desarrollo de nuevas moléculas con efectos antinociceptivos específicos ha revolucionado el manejo del dolor, creando el concepto de analgesiadirigida al órgano blanco (at-site pain targets). En esta breve revisión se discuten algunos de los mecanismos de acción analgésica de antiguos y de nuevos medicamentos que podemos utilizar en las personas con dolor agudo postoperatorio, con dolor crónicono oncológico y en dolor secundario al cáncer.

Despite major advances in the understanding and treatment of acute and chronic pain, this entity continues to be a plague to mankind. It was considered that more than 1’500,000’000,000 human beings suffer from moderate to severe chronic pain, which means a high health and economic costs, even in the most developed countries. For centuries mankind has used remedies to relieve pain suffering and although the use of opioids and nonsteroidal anti-inflamma tory drugs revolutionized the management of pain, their side effects are a restriction limiting its use and therapeutic efficacy. The knowledge of novel nociceptors and their ligands revolutionized our understanding of pain, facilitating its prevention and treatment. The proper use of analgesic and co-adyuvant drugs with selective actions on specific receptors of the multiple and complex pain pathways is based on the understanding of the pain mechanisms involved in molecular interaction on nociceptor receptors such as sodium and potassium membrane channels, purinergic, NMDA, and cannabinoid receptors, among many others. The rediscovery of the ancient analgesic properties of drugs and development of new molecules with specific antinociceptive effects has revolutionized pain management, creating the concept of analgesia addressed to the target organ (at-site pain targets). In this brief review we discuss some of the mechanisms of analgesic action of old and new drugs that can be used in people with acute postoperative pain, chronic noncancer pain and pain secondary to cancer.