Reversal of Opioid-induced Respiratory Depression With Opioid Antagonists

This study is testing whether a drug that reverses opioid effects (an opioid antagonist) can safely and quickly reverse breathing problems caused by opioid use, to help address the opioid overdose crisis. **You may be eligible if...** - You are a healthy volunteer between 18 and 70 years old - Your body mass index (BMI) is between 18 and 30 - You are in good general health with no significant medical conditions - Women of childbearing age must test negative for pregnancy and agree to use contraception **You may NOT be eligible if...** - You have significant health conditions (heart, liver, kidney, lung problems) - You are pregnant or breastfeeding - You have a history of opioid dependence or substance use disorder - You are taking medications that could interfere with the study drugs Talk to your doctor to see if this trial is right for you.