Xylazine administration is used for sedation, anesthesia, muscle relaxation, and analgesia. Opioids produce analgesia and often feelings of euphoria in users. It is more effective than opioids and other common modalities of analgesia in childbirth. When combined with opioids it increases the level of analgesia (pain relief) obtained. Treatment is usually with intravenous antibiotics, analgesia and washout and/or aspiration of the joint. Its primary actions of therapeutic value are analgesia and sedation. Endocannabinoids are involved in placebo induced analgesia responses. Sublingual fentanyl solves quickly and is absorbed through the sublingual mucosa to provide rapid analgesia. Inhalation sedation is also sometimes referred to as "relative analgesia". Isoflurane reduces pain sensitivity (analgesia) and relaxes muscles. Transdermal delivery systems are also under consideration to induce local skin analgesia. Activation of the KOR is associated with spinal analgesia, miosis (pinpoint pupils), and psychotomimetic effects. All these effects work synergistically to induce analgesia. The receptors are responsible for supra-spinal analgesia. Current recommendations stress the need to use topical and/or oral analgesia and topical antibiotics.