Tramadol is widely used globally and is the second most prescribed opioid in the United
States. It treats moderate to severe pain but lethal opioid-induced respiratory depression is …

Opioid-associated overdoses and deaths due to respiratory depression are a major public
health problem in the US and other Western countries. In the past decade, much research …

Background and Purpose GPCRs can signal through both G proteins and β‐arrestin2. For
the μ‐opioid receptor, early experimental evidence from a single study suggested that G …

Morphine and fentanyl are among the most used opioid drugs that confer analgesia and
unwanted side effects through both G protein and arrestin signaling pathways of μ-opioid …

The concept of ligand bias at G protein-coupled receptors broadens the possibilities for
agonist activities and provides the opportunity to develop safer, more selective therapeutics …

Drugs targeting the G protein-coupled μ-opioid receptor (μOR) are the most effective
analgesics available but are also associated with fatal respiratory depression. While some …

Opioids are perhaps the most effective analgesics in medicine. However, between 1999 and
2018, over 400,000 people in the United States died from opioid overdose. Excessive …

Opioids are an important tool in the treatment of pain, but opioid overdose has become a
serious health issue. Most opioid-related deaths are caused by respiratory depression, and …

BACKGROUND: Levorphanol is a potent analgesic that has been used for decades. Most
commonly used for acute and cancer pain, it also is effective against neuropathic pain. The …

The search for safer opioid analgesics that have reduced liability for tolerance, addiction,
and lethal overdose due to respiratory depression has met with little success for well over a …