This clinical trial is focused on studying the effects of certain medications on reversing breathing problems caused by opioids. The diseases being studied include opioid use disorder and the trial also involves healthy volunteers. The medications being tested are nalmefene hydrochloride, naloxone hydrochloride, fentanyl citrate, sufentanil, and ondansetron hydrochloride dihydrate. These medications are used in different forms such as injections and nasal sprays.
The purpose of the study is to understand how these medications can help reverse the breathing difficulties that opioids can cause. Participants will receive either the medication or a placebo, and their breathing will be monitored to see how well the medications work. The study will involve both people who are new to opioids and those who have been using them for a long time.
Throughout the study, participants will receive the medications through injections or nasal sprays, and their breathing will be closely observed. The study aims to gather information on how quickly and effectively these medications can reverse the effects of opioids on breathing. This research is important for improving treatments for people who experience breathing problems due to opioid use.



The Netherlands