Buprenorphine, an analogue of thebaine, is a Schedule III opioid in the United States used for opioid-use disorder and as an analgesic. Research has shown drugs like buprenorphine have a complicated pharmacology with characteristics that challenge traditional definitions of terms like agonist, antagonist, and efficacy. Buprenorphine has a high affinity for the mu (MOR), delta (DOR), kappa (KOR), and intermediate for the nociceptin opioid receptors (NOR). Buprenorphine is generally described as a partial MOR agonist with limited activity and decreased response at the mu-receptor relative to full agonists. In opioid naïve patients, the drug’s analgesic efficacy is equivalent to a full MOR agonist, despite decreased receptor occupancy and the “ceiling effect” produced from larger doses. Some argue buprenorphine’s effects depend on the endpoint measured, as it functions as a partial agonist for respiratory depression, but a full-agonist for pain. Buprenorphine’s active metabolite, norbuprenorphine, attenuates buprenorphine's analgesic effects due to NOR binding and respiratory depressant effects. The method of administration impacts efficacy and tolerance when administered for analgesia. There have been eleven-thousand reports involving buprenorphine and minors (age < 19) to US poison control centers, the preponderance (89.2%) with children. The consequences of prenatal buprenorphine exposure in experimental animals and humans should continue to be carefully evaluated. In conclusion, buprenorphine’s characterization as only a partial mu-agonist is an oversimplification. Contemporary research shows the traditional explanation of the pharmacology of buprenorphine does not take into account changes to receptor theory, pharmacological terminology, route of administration, and biologically active major metabolites.

Objective: To evaluate the changing pattern of distribution of Schedule II and III opioids, barbiturates, and stimulants to veterinary educational institutions in the United States. Design: Longitudinal study. Sample: Veterinary teaching institutions that use Schedule II and III drugs. Procedures: Distribution of controlled substances to veterinary teaching institutions was obtained from the Drug Enforcement Administration’s Automated Reports and Consolidated Orders System (ARCOS) for opioids (e.g. methadone, fentanyl, codeine), barbiturates (pentobarbital, butalbital), and stimulants (amphetamine, methylphenidate, lisdexamfetamine) from 2006 - 2019. Opioids were converted to their morphine milligram equivalents (MME) for evaluation over time. Results: Controlled substance distribution to veterinary schools exhibited dynamic, and agent specific, changes. The total MME for eleven opioids peaked in 2013 and decreased by 17.3% in 2019. Methadone accounted for two-fifths (42.3%) and fentanyl over one-third (35.4%) of the total MME in 2019. Pentobarbital distribution was greatest by weight of all substances studied and peaked in 2011 at 69.4 kg. Stimulants underwent a pronounced decline and were very modest by 2014. Conclusions and Clinical Relevance: Opioids by total MME in veterinary teaching practice have undergone more modest changes than opioids used with humans. Hydrocodone, codeine and recently fentanyl use have declined while methadone increased. Stimulant distribution decreased to become negligible. Together, this pattern of findings warrant continued monitoring.

Rationale:First discovered in 1990, the endocannabinoid system (ECS) was initially shown to have an intimate relationship with central areas of the nervous system associated with pain, reward, and motivation. Recently, however, the ECS has been extensively implicated in the cardiovascular system with contractility, heart rate, blood pressure, and vasodilation. Emerging data demonstrates modulation of the ECS plays an essential role in cardio metabolic risk, atherosclerosis, and can even limit damage to cardiomyocytes during ischemic events.Patient Concerns:This case describes a 63-year-old male who presented to a primary care physician for a medical cannabis (MC) consult due to unstable angina (UA) not relieved by morphine or cardiac medications; having failed all first- and second-line poly-pharmaceutical therapies. The patient reported frequent, unprovoked, angina and exertional dyspnea.Diagnosis:Having a complex cardiac history, the patient first presented 22 years ago after a suspected myocardial infarction (MI). He re-presented in 2010 and underwent stent placement at that time for inoperable triple-vessel coronary artery disease (CAD) which was identified via percutaneous transluminal coronary angioplasty. UA developed on follow up and, despite medical management over the past 6 years, his UA became progressively debilitating.Interventions and Outcomes:In conjunction with his standard cardiac care, patient had a gradual lessening of UA related pain, including frequency and character, after using an edible form of medical cannabis (MC) (1:1 CBD:THC). Following continued treatment, he ceased long term morphine treatment and describes the pain as no longer crippling. As demonstrated by his exercise tolerance tests, the patient experienced an improved functional capacity and reported an increase in his daily functioning, and overall activity.Lessons:This case uniquely highlights MC in possibly reducing the character, quality, and frequency of UA; while concordantly improving functional cardiac capacity in a patient with CAD. Additional case reports are necessary to verify this.

Diffuse intrinsic pontine glioma (DIPG) is recognized as a pediatric brainstem cancer with a 0% survival rate. On a molecular basis, DIPG commonly results from mutations in histone H3, specifically a mutation in the H3K27M gene, that promotes tumorigenesis and results in presentation of this fatal brainstem tumor. DIPG is challenging to treat, as surgical intervention is inefficacious due to the location where the glioma resides. To date, traditional treatments such as radiation, chemotherapy, and immunotherapy have not increased survival rates and have only been successful at relieving symptoms. Future therapeutic approaches such as proton beam radiation, Chimeric Antigen Receptor T Cell (CAR-T) immunotherapy, and alternative epigenetic pharmaceuticals are under investigation for potential benefits. Various clinical trials have also explored these treatment procedures to discover potential increases in survival rates in both animal and human studies. In this review, we will evaluate the pathology and molecular characteristics of DIPG, the current and future approaches to DIPG treatment; and, lastly, we will discuss clinical trials that have been completed to develop successful treatment options.

The opioid epidemic is an ongoing public health crisis, and the United States health system is overwhelmed with increasing numbers of opioid-related overdoses. Methocinnamox (MCAM) is a novel mu-opioid receptor antagonist with an extended duration of action and potential to reduce the burden of the opioid epidemic through overdose rescue and could treat opioid use disorder (OUD) long-term. We compared the efficacy and effects of MCAM to the current treatments available to treat OUD including naloxone, naltrexone, methadone, and buprenorphine which have their own limitations including short duration of action, patient non-compliance, and diversion. A literature review was conducted using PubMed and Google Scholar databases covering the history of the opioid epidemic, pain receptors, current OUD treatments and the novel drug MCAM. MCAM could potentially be used as both a rescue and long-term treatment for opioid misuse. This is due to its pseudo-irreversible antagonism of the mu opioid receptor, abnormally long duration of action of nearly two weeks, and the possibility of using kappa or delta opioid receptor agonists for pain management during OUD treatment. MCAM’s novel pharmacokinetic and pharmacodynamic properties open a new avenue for treating the opioid crisis.