Chronic Pain: Causes, Types, and Treatment Options

Pain is supposed to be temporary. It's your body's alarm system, telling you something is wrong so you can fix it. But for roughly 50 million Americans living with chronic pain, the alarm never shuts off. The injury heals, the surgery is long past, or there was never a clear cause to begin with, and the pain just continues. Week after week, month after month, reshaping your sleep, your mood, your work, and your ability to show up for the people around you.

Chronic pain, defined as pain persisting for 3 months or longer, is the leading cause of disability in the United States, according to the CDC. About 20% of U.S. adults experience it. It's not in your head. It's not a character weakness. And it's not something you should just learn to live with, because there are management strategies most people haven't been offered yet.

Key Facts

• Prevalence: 50.2 million U.S. adults (20.5%) have chronic pain; 17.1 million (6.9%) have high-impact chronic pain that limits daily activities (CDC, 2023)
• Typical onset: Varies widely; can follow injury, surgery, or develop without a clear initiating event
• Commonly confused with: Acute pain (resolves with healing), somatization, medication-seeking behavior
• When to see a provider: If pain has persisted for 3 or more months and is affecting your function, sleep, or quality of life

Types and Symptoms of Chronic Pain

Chronic pain isn't one condition. It's a category that encompasses dozens of conditions, each with different mechanisms, locations, and treatment responses.

Nociceptive pain (tissue-based):

• Originates from ongoing tissue damage or inflammation
• Includes osteoarthritis, inflammatory arthritis, chronic low back pain from structural causes
• Usually described as aching, throbbing, or sharp
• Tends to respond to anti-inflammatory approaches

Neuropathic pain (nerve-based):

• Results from damage or dysfunction in the nervous system itself
• Includes diabetic neuropathy, post-herpetic neuralgia (after shingles), radiculopathy, small fiber neuropathy
• Often described as burning, shooting, electric, or tingling
• Can occur without an ongoing tissue injury
• Frequently responds poorly to standard painkillers

Nociplastic pain (central sensitization):

• Pain amplified by the central nervous system without clear tissue or nerve damage
• Includes fibromyalgia, chronic widespread pain, some cases of chronic pelvic pain and irritable bowel syndrome
• Often involves pain in multiple areas, fatigue, sleep disturbance, and cognitive symptoms ("fibro fog")
• Standard imaging and lab tests typically come back normal, which doesn't mean the pain isn't real

Complex Regional Pain Syndrome (CRPS):

• A specific chronic pain condition usually following injury or surgery
• Involves severe, burning pain disproportionate to the original injury, along with swelling, skin changes, temperature changes, and motor dysfunction
• One of the most severe chronic pain conditions and one that has shown response to ketamine in clinical studies

Common symptoms across chronic pain types:

• Pain that persists beyond expected healing time
• Sleep disruption (pain keeps you awake; poor sleep worsens pain, a vicious cycle)
• Fatigue and reduced stamina
• Mood changes: depression and anxiety co-occur with chronic pain in 30-50% of cases
• Reduced physical activity and deconditioning
• Difficulty concentrating
• Social withdrawal
• Functional impairment in work and daily activities

What Causes Chronic Pain

Chronic pain can begin with a clear injury or illness and persist after the original problem has resolved. It can also develop without an identifiable cause. In either case, the pain becomes self-sustaining through changes in the nervous system.

Peripheral sensitization: Nerve endings in the affected area become more sensitive to stimuli, lowering the threshold for pain signals.

Central sensitization: The spinal cord and brain amplify pain signals, causing normal sensations (light touch, mild pressure) to register as painful (allodynia) or painful stimuli to feel much worse than they should (hyperalgesia).

Psychosocial factors that influence chronic pain (not cause, but influence):

• Catastrophizing (expecting the worst outcome)
• Fear-avoidance: avoiding activity due to fear of worsening pain, which leads to deconditioning, which worsens pain
• Depression and anxiety (bidirectional relationship)
• Childhood adversity and trauma
• Social isolation
• Work dissatisfaction and financial stress

These factors don't mean the pain is "psychological." They mean that pain is a complex experience influenced by biological, psychological, and social factors, all of which are legitimate treatment targets.

How Chronic Pain Is Diagnosed

There's no single test that diagnoses chronic pain. Diagnosis involves identifying the type of pain, its probable mechanism, contributing factors, and functional impact.

A thorough evaluation includes:

• Detailed pain history: onset, location, character, aggravating and relieving factors, duration, progression
• Review of prior treatments and their effectiveness
• Physical examination
• Imaging (X-ray, MRI, CT) when structural causes are suspected, though normal imaging doesn't rule out pain
• Nerve conduction studies and EMG for suspected neuropathic pain
• Lab work to rule out inflammatory, metabolic, or autoimmune causes
• Screening for co-occurring depression and anxiety
• Functional assessment: how does pain affect work, sleep, mobility, and daily activities
• Medication history including opioid use, which is important for treatment planning

Treatment Options for Chronic Pain

Chronic pain management is rarely about finding one solution. It's about building a combination of approaches that together reduce pain, improve function, and restore quality of life.

Foundational approaches:

• Physical therapy and movement. Graduated exercise, stretching, and strengthening reduce pain sensitivity and reverse deconditioning. Movement is medicine for chronic pain, even when it feels counterintuitive.
• Cognitive Behavioral Therapy for pain (CBT-CP). Addresses catastrophizing, fear-avoidance, and the psychological factors that amplify pain. Strong evidence base, particularly for fibromyalgia and chronic back pain.
• Sleep optimization. Pain disrupts sleep, and poor sleep worsens pain. Breaking this cycle is a treatment priority.

Medication:

• Non-opioid analgesics: Acetaminophen, NSAIDs (for inflammatory pain), topical lidocaine, topical capsaicin
• Neuropathic pain medications: Gabapentinoids, SNRIs, and tricyclic antidepressants are first-line for neuropathic pain
• Muscle relaxants for pain with significant muscle spasm
• Opioids are appropriate in selected chronic pain cases but carry significant risks including tolerance, dependence, and hyperalgesia. Current guidelines recommend them as a last resort after other options have been tried.

Procedural interventions:

• Nerve blocks, epidural injections, and joint injections
• Radiofrequency ablation for specific nerve pain
• Spinal cord stimulation for refractory neuropathic pain

Ketamine therapy for chronic pain:

Ketamine acts on NMDA receptors in the central nervous system, which play a key role in central sensitization and pain amplification. For certain chronic pain conditions, particularly CRPS, neuropathic pain, and fibromyalgia, ketamine has shown promise in reducing pain and improving function.

• Ketamine is used off-label for chronic pain. It is not FDA-approved for this indication.
• It is a Schedule III controlled substance administered only under medical supervision.
• Clinical studies have demonstrated benefit for CRPS (Sigtermans et al., Pain, 2009) and other centrally sensitized pain conditions, though individual responses vary.
• At Ascend, ketamine therapy for chronic pain is evaluated on a case-by-case basis. Not every chronic pain patient is a candidate.

When to See a Provider

If pain has persisted for more than 3 months and is affecting your sleep, your ability to work, your mood, or your relationships, you should be in a comprehensive pain management conversation, not just taking pills and hoping.

Seek a provider if:

• Your current pain management plan isn't working
• You've been on opioids long-term and want to explore alternatives
• You have neuropathic pain that standard medications haven't controlled
• You've been diagnosed with fibromyalgia, CRPS, or chronic widespread pain and haven't been offered a multimodal treatment plan
• Your chronic pain is accompanied by depression, anxiety, or sleep problems that aren't being addressed
• You're interested in exploring whether ketamine therapy might be appropriate for your condition

How Ascend Approaches Chronic Pain

At Ascend Mind and Body, chronic pain treatment involves our ketamine therapy program for qualifying patients and coordination with our primary care practice for ongoing management.

Anna Stouffer, PMHNP-BC evaluates patients for ketamine therapy candidacy, which involves a thorough review of your pain history, prior treatments, co-occurring conditions, and goals. Not every patient with chronic pain is a candidate for ketamine. We're looking for conditions where central sensitization plays a significant role and where standard treatments have been insufficient.

For patients whose chronic pain coexists with depression (as it often does), we coordinate psychiatric and pain management simultaneously. Treating one without the other rarely produces good outcomes.

Ketamine for chronic pain is typically a cash-pay service. Consultation and evaluation appointments may be covered by insurance depending on your plan. Visit our new patients page to schedule.

This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider for diagnosis and treatment.

This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider for diagnosis and treatment.