Opioid misuse and its rising rates of morbidity and associated mortality is an increasing area of concern worldwide. The licit/illicit consumption of opioids ranging from plant-based substances and pharmaceutical drugs (particularly analgesia) to the new synthetic opioids, has brought opioid use disorder (OUD) back to the public health concerns, including not only prevention but also availability of evidence-based treatments. Agonist opioids have demonstrated by long high efficacy and effectiveness for OUD treatment. Although methadone has been the more prescribed drug in most of the countries where opioid agonist treatment is available, other agonist opioids can be prescribed. We will present a start of the art of other agonist opioids available for the treatment of OUD, emphasizing in the differences among them, in line with of personalizing treatment in addiction. We will focus on morphine slow release, buprenorphine (with or without naloxone, sublingual or long-lasting) and diacetylmorphine.

Introduction: Acute pain represents one of the most common reasons for emergency department (ED) visits. In the opioid epidemic that North America faces, there is a significant demand for novel pain control modalities that are both safe and effective. Regional anesthesia techniques have revolutionized perioperative pain management, and they are currently thought to be indicated for acute pain relief in the ED. The erector spinae plane block (ESPB) is a novel regional block that has the ability to block multidermatomal sensation, including cervical, thoracic and lumbar regions, depending on the vertebral level at which the anesthetic is injected along the erector spinae muscle. Under ultrasound guidance, the landmarks involved are easy to identify, and there are no vital structures in the immediate vicinity of the site of injection. By reviewing the literature on ESPB, this review aims to summarize all its indications and efficacy for acute pain management in the ED. Methods: In April 2019, PUBMED, EMBASE, MEDLINE as well as CINAHL databases were systematically searched for articles discussing the use of ESPB in the ED. In compliance with the PRISMA guidelines, the search results were selected against inclusion and exclusion criteria. Due to the novelty of the block, all types of articles were included. Results: Ten studies on 7 different indications have been published on the use of ESPB in the ED. It is currently most commonly used for rib and spine fractures. Other indications include, mechanical back pain, burn injuries, herpes zoster, renal colic, and acute pancreatitis. ESPB was administered at the vertebral level of region of most pain, unilaterally or bilaterally for complete dermatomal block. It was injected as a single or continuous block - in the seated, lateral, or prone position. All of the studies demonstrate a significant reduction in pain. Furthermore, it has been reported to improve respiratory function, and it has not been associated with any complications following administration. Conclusion: This review shows initial data on the promising effect of ESPB in acute pain management in the ED. Current evidence shows its effectiveness and safety for the most common presenting cases of pain, such as rib and spine fracture, mechanical back pain, burn injuries, herpes zoster, renal colic, as well as acute pancreatitis. ESPB is flexible in administration and relatively easy to perform under ultrasound guidance.