Who makes Unrestricted Fentanyl?

Unrestricted Fentanyl is developed by Virginia Commonwealth University.

What development phase is Unrestricted Fentanyl in?

Unrestricted Fentanyl is FDA-approved (marketed).

What are the side effects of Unrestricted Fentanyl?

Common side effects include Respiratory depression, Sedation, Nausea and vomiting, Constipation, Dizziness, Pruritus.

Last reviewed 2026-04-22 · How we verify

Unrestricted Fentanyl

Virginia Commonwealth University · FDA-approved active Small molecule

Fentanyl is a synthetic opioid agonist that binds to mu-opioid receptors in the central nervous system to produce analgesia and sedation.

Fentanyl is a synthetic opioid agonist that binds to mu-opioid receptors in the central nervous system to produce analgesia and sedation. Used for Moderate to severe acute and chronic pain, Cancer pain, Perioperative anesthesia and analgesia.

At a glance

Generic name	Unrestricted Fentanyl
Also known as	Unlimited intraoperative opiates
Sponsor	Virginia Commonwealth University
Drug class	Synthetic opioid agonist
Target	Mu-opioid receptor (OPRM1)
Modality	Small molecule
Therapeutic area	Pain management
Phase	FDA-approved

Mechanism of action

Fentanyl activates mu-opioid receptors throughout the brain and spinal cord, inhibiting pain signal transmission and modulating emotional responses to pain. It is approximately 50-100 times more potent than morphine. The term 'Unrestricted Fentanyl' likely refers to a formulation or research context without standard regulatory restrictions, though the underlying mechanism remains opioid receptor agonism.

Approved indications

Moderate to severe acute and chronic pain
Cancer pain
Perioperative anesthesia and analgesia

Common side effects

Respiratory depression
Sedation
Nausea and vomiting
Constipation
Dizziness
Pruritus

Key clinical trials

Multimodal Analgesia in Cardiac Surgery (Pilot Study) (PHASE4)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Source	Used for
ClinicalTrials.gov	Trial enrolment, design, endpoints, results

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Unrestricted Fentanyl CI brief — competitive landscape report
Unrestricted Fentanyl updates RSS · CI watch RSS
Virginia Commonwealth University portfolio CI