Tools to Reduce & Manage Pain: Insights from Dr. Sean Mackey
Summary
Dr. Sean Mackey, Chief of the Division of Pain Medicine at Stanford University, explains the neuroscience of pain from nociception through brain processing, distinguishing the sensory and emotional components of the pain experience. The conversation covers how pain is shaped by psychological state, early life experiences, and individual variability, while providing practical tools ranging from over-the-counter medications and physical interventions to mindfulness and cognitive reframing. A key theme throughout is understanding the critical difference between pain that signals harm versus pain that is merely uncomfortable.
Key Takeaways
- Pain is a brain event, not a body event — signals from nociceptors in the periphery are not pain themselves; pain only arises when those signals converge in the brain.
- NSAIDs (ibuprofen, naproxen, aspirin) are not technically painkillers — they are anti-inflammatory and anti-hyperalgesic drugs that reduce peripheral sensitization, not the raw pain signal itself.
- Rubbing, shaking, or running water over an injury works by activating A-beta touch fibers that modulate nociceptive signals at the spinal cord level — a free and effective form of neuromodulation.
- Pain inhibits pain (conditioned pain modulation): activating a painful stimulus at one site can inhibit pain at a separate site via brainstem descending pathways.
- The hurt vs. harm distinction is one of the most clinically important concepts in pain management — understanding that pain does not always equal tissue damage can dramatically change behavior and outcomes.
- Attentional distraction and mindfulness are both effective but engage different neural circuits; mindfulness-based stress reduction (MBSR) has strong evidence for anxiety, depression, and pain.
- Catastrophizing is among the strongest predictors of worsening pain and poor treatment response.
- Anger, anxiety, and depression all amplify pain; “anger in” (suppressed, simmering anger) appears worse than outwardly expressed anger.
- Exercise raises pain threshold over time by building inhibitory tone in pain-processing circuits.
- Anti-inflammatory nutrition is a critically underappreciated tool in managing chronic pain.
Detailed Notes
What Is Pain?
- Pain is defined as a complex, subjective, sensory and emotional experience that protects us from injury.
- It affects approximately 100 million Americans and costs ~$500 billion/year in the US.
- Chronic pain is often called the “invisible disease” — there may be no visible injury, making it frequently misunderstood.
- Pain is highly individual — your pain experience is shaped by your brain, emotions, memories, beliefs, and context.
Nociception vs. Pain
- Nociceptors in skin, soft tissue, and deep tissue detect heat, cold, pressure, and pH changes (e.g., from inflammation).
- Signals travel via two fiber types:
- A-delta fibers: fast-conducting; responsible for sharp, immediate pain (e.g., stepping on a tack).
- C fibers: slow-conducting; responsible for dull, aching pain; converge on emotional brain regions, conveying unpleasantness.
- Signals reach the spinal cord, are modulated, then ascend to the brain — pain only exists as a brain-level experience.
- The outdated Cartesian “one-to-one” model (stimulus → pain) is incorrect; the brain’s emotions, memories, cognitions, and expectations all shape the final pain experience.
Brain Networks and Pain
- There is no single “pain center” in the brain.
- Pain involves a distributed network including the insular cortex, cingulate cortex, and amygdala (formerly called the “pain matrix”).
- Brain-based biomarkers for pain are an active area of research at Stanford.
Over-the-Counter Pain Medications
| Medication | Type | Key Notes |
|---|---|---|
| Ibuprofen | NSAID (COX inhibitor) | Short half-life; take up to 3x/day; needs food and fluids |
| Naproxen (Naprosyn) | NSAID | Twice daily; individual variability — works better for some than ibuprofen |
| Aspirin (81mg) | NSAID / antiplatelet | Baby aspirin daily for heart health; 325mg becomes anti-inflammatory |
| Acetaminophen (Tylenol) | Centrally acting | Safe on stomach; max ~4g/day; avoid with heavy alcohol use or liver issues |
| Celecoxib | COX-2 inhibitor (Rx only) | Less GI irritation; prescription required |
- NSAIDs are anti-hyperalgesic, not true analgesics — they reduce sensitization after injury but do not block normal pain signals.
- NSAIDs may delay fracture and tissue healing by blocking inflammation — use at the lowest effective dose.
- Caffeine can potentiate the analgesic response and is effective for headaches/migraines via the prostaglandin pathway; take with food if combining with NSAIDs.
- Timing guidance: Take ibuprofen no more than 3x/day; naproxen twice daily; always with food and fluids.
- People with GI, kidney, heart, or bleeding issues should consult a clinician before using NSAIDs.
Gate Control Theory and Mechanical Interventions
- Gate control theory of pain (Melzack & Wall, 1960s): touch fibers (A-beta) synapse onto nociceptive fibers in the spinal cord and inhibit pain signal transmission.
- Rubbing, shaking, or running water over an injured area activates A-beta fibers → modulates pain signals at the spinal cord → reduces perceived pain.
- Swearing has been shown in studies to reduce pain perception (mechanism unclear).
- TENS (Transcutaneous Electrical Nerve Stimulation): devices that apply electrical buzzing to skin, activating A-beta fibers to achieve spinal cord-level neuromodulation.
- A kiss or comforting touch reduces pain both through touch fiber activation and positive emotional salience.
Conditioned Pain Modulation (CPM)
- Pain inhibits pain: applying a painful stimulus at a site distal to the primary pain activates brainstem descending inhibitory pathways to the spinal cord, reducing the primary pain.
- Originally described as Diffuse Noxious Inhibitory Control (DNIC) (Le Bars, ~1978) in rodent models.
- CPM is impaired in certain chronic pain conditions, such as fibromyalgia.
Heat and Cold Therapy
- Traditional guideline: Cold for the first ~48 hours after acute injury; heat thereafter.
- Cold reduces inflammatory chemical release (prostaglandins, cytokines, histamines), slows nerve firing rate, and reduces nociceptive signal frequency.
- Heat increases blood flow, relaxes muscles, and promotes healing.
- Individual variability is high — use whichever works best for the individual.
- Safety: Do not apply ice directly to skin for extended periods (frostbite risk); numbing the area to the point of anesthesia is a reasonable endpoint for cold application.
Pain Thresholds and Individual Variability
- Pain threshold = the stimulus intensity at which a sensation first becomes painful.
- Shaped by: anxiety, past trauma, early life experiences, beliefs, expectations, emotional state, context, and social cues.
- Men vs. women: On average, men have slightly higher heat pain thresholds, but within-group variability vastly exceeds between-group differences — the distributions heavily overlap.
- Social context matters: Studies show pain thresholds in men rose when an attractive female researcher administered the stimulus.
- Exercise raises pain thresholds over time, likely by increasing inhibitory tone in pain circuits.
- Cognitive training (reframing, mindfulness) can also change thresholds.
Psychological Approaches to Pain
Attentional Distraction
- Engages prefrontal cortex and cingulate cortex networks.
- Strategies: reading, socializing, walking, engaging activities.
- Biggest challenge: nighttime, when distraction is unavailable and chronic pain