OPEN Foundation

Day: 1 September 2016

Ketamine: Future Treatment For Unresponsive Depression?

Abstract

Major Depressive Disorder (MDD) is a debilitating mental health condition which accounts for a significant portion of worldwide disability. Historically, the suggested pharmacotherapy to treat MDD have been monoaminergic-acting antidepressants, such as SSRIs or SNRIs. These drugs can provide relief, but often take weeks to noticeably improve depressive symptoms and are not always effective, leading to a condition known as Treatment-Resistant Depression (TRD). It is believed that 50% MDD sufferers in Ireland suffer from TRD, and thus the development of improved pharmacotherapies is necessary. One emerging therapy is low dose, intravenous (R-S)-Ketamine (ketamine). While the molecular basis of ketamine’s therapeutic effect has not been fully determined, it has shown to effectively and swiftly mitigate the symptoms of TRD. Barriers do exist preventing the legal prescription of ketamine, including its questionable safety profile and risk of inducing dependence. Despite this, ketamine remains a promising pharmacotherapy for TRD and further investigation is required.

Frere, M., & Tepper, J. (2016). Ketamine: Future Treatment For Unresponsive Depression?. Irish Medical Journal. 10147/620895
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Ibogaine for treating drug dependence. What is a safe dose?

Abstract

The indole alkaloid ibogaine, present in the root bark of the West African rain forest shrub Tabernanthe iboga, has been adopted in the West as a treatment for drug dependence. Treatment of patients requires large doses of the alkaloid to cause hallucinations, an alleged integral part of the patient’s treatment regime. However, case reports and case series continue to describe evidences of ataxia, gastrointestinal distress, ventricular arrhythmias and sudden and unexplained deaths of patients undergoing treatment for drug dependence. High doses of ibogaine act on several classes of neurological receptors and transporters to achieve pharmacological responses associated with drug aversion; limited toxicology research suggests that intraperitoneal doses used to successfully treat rodents, for example, have also been shown to cause neuronal injury (purkinje cells) in the rat cerebellum. Limited research suggests lethality in rodents by the oral route can be achieved at approximately 263mg/kg body weight. To consider an appropriate and safe initial dose for humans, necessary safety factors need to be applied to the animal data; these would include factors such as intra- and inter-species variability and for susceptible people in a population (such as drug users). A calculated initial dose to treat patients could be approximated at 0.87mg/kg body weight, substantially lower than those presently being administered to treat drug users. Morbidities and mortalities will continue to occur unless practitioners reconsider doses being administered to their susceptible patients.
Schep, L. J., Slaughter, R. J., Galea, S., & Newcombe, D. (2016). Ibogaine for treating drug dependence. What is a safe dose?. Drug and alcohol dependence166, 1-5. 10.1016/j.drugalcdep.2016.07.005
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The Resurrection Of Psychedelic Psychiatry And Its Role In Addiction Treatment

Abstract

Psychedelic psychiatry, a field which was previously popular between 1950-1970, has recently received a renewed interest as several recent studies have highlighted the potential role of hallucinogens in the treatment of addictions and various mental illnesses. This paper looks at evidence supporting the use of LSD, ibogaine and ayahuasca to treat various addictions and discusses the barriers to further exploration of the therapeutic potential of psychedelic substances.

Skocylas, R. (2016). The resurrection of psychedelic psychiatry and its role in addiction treatment. UBC Medical Journal, 8(1).
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