Last reviewed 2026-04-23 · How we verify

Tramadol PR oral

Tramadol is a synthetic opioid analgesic that binds to mu opioid receptors and also inhibits the reuptake of norepinephrine and serotonin to provide pain relief.

Tramadol is a synthetic opioid analgesic that binds to mu opioid receptors and also inhibits the reuptake of norepinephrine and serotonin to provide pain relief. Used for Moderate to moderately severe chronic pain.

At a glance

Mechanism of action

Tramadol works through dual mechanisms: it acts as a weak mu opioid receptor agonist to reduce pain signaling, and simultaneously inhibits the reuptake of norepinephrine and serotonin in the central nervous system, enhancing descending pain inhibitory pathways. The PR (prolonged-release) formulation provides extended drug delivery over 24 hours, allowing for once or twice-daily dosing for chronic pain management.

Approved indications

• Moderate to moderately severe chronic pain

Common side effects

• Nausea
• Dizziness
• Constipation
• Headache
• Somnolence
• Vomiting
• Seizures

Key clinical trials

• A Phase 3 Study of Tanezumab for Chronic Low Back Pain (PHASE3)
• Comparison of the Efficacy, Tolerability and Safety of actiTENS to Those of Level 2 Analgesic Treatments. (NA)

Primary sources

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Competitive intelligence

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

• Tramadol PR oral CI brief — competitive landscape report
• Tramadol PR oral updates RSS · CI watch RSS
• Pfizer portfolio CI