The Cost of Waiting: What Happens When CRPS Is Left Untreated

Joseph was 55, a roofer, with the hands and the work ethic that go with three decades on ladders. One slip, one fall, one injury that was not correctly identified — and the trajectory of his life changed.

What followed was complex regional pain syndrome. What made it catastrophic was not the diagnosis. It was the eighteen months of nothing that came after it.

What CRPS is, and why delay is not neutral

Complex regional pain syndrome is a disorder in which the nervous system’s response to an injury fails to switch off after the tissue has healed. Pain becomes disproportionate to the original injury, then continuous, then accompanied by changes in temperature, colour, sweating and movement in the affected limb.

We have written elsewhere about how CRPS is actually diagnosed using the Budapest criteria and about whether it can be cured. This article is about a different question, and a harder one: what happens in the months when nothing is done.

The answer is that CRPS is not a condition that waits politely. Persistent pain signalling drives changes in the central nervous system — a process usually described as central sensitization, in which the spinal cord and brain amplify rather than dampen incoming signals. The longer that runs, the more established it becomes, and the less responsive the condition is to any treatment.

Early intervention is not a preference in CRPS. It is the treatment variable with the most leverage.

What Joseph was offered

Anti-inflammatories. A referral to physical therapy. And an explicit refusal to consider anything stronger, on the grounds of addiction risk.

Each of those has a defensible rationale in isolation. Together, as the entire plan, they amounted to a decision not to treat.

• NSAIDs reduce peripheral inflammation. CRPS pain is substantially neuropathic and centrally maintained, and NSAIDs do not reach it. They also carry cardiovascular, renal and gastrointestinal risk on long-term use.
• Physical therapy is genuinely valuable in CRPS — early, and graded carefully. Applied to an established, highly sensitized limb without pain control first, movement hurts, the patient withdraws, the limb deconditions, and the pain deepens. The therapy was not wrong. The sequence was.
• Doing nothing else was treated as the safe option. It was not.

The part that is easy to miss: pain is a brain exposure

The most under-appreciated consequence of untreated chronic pain is cognitive.

Continuous nociceptive input drives activation of microglia — the central nervous system’s resident immune cells — and sustained release of inflammatory signalling molecules. Persistent pain also keeps the stress axis switched on, with chronically elevated cortisol. Both processes are unfavourable to the hippocampus and prefrontal cortex, the regions that carry memory and executive function.

The observational literature has repeatedly found associations between chronic pain and later cognitive decline, with reported effect sizes varying by cohort and by how pain was defined. These are associations rather than demonstrated causation, and they should be read that way. But the direction is consistent, and it reframes the clinical question: leaving pain untreated is itself an exposure with a cost, not a neutral holding position.

We covered the mechanism in more depth in what untreated chronic pain does to the brain.

What “treating it” actually means here

This is where the conversation usually goes wrong, so it is worth being unambiguous.

Treating CRPS early does not mean reaching for opioids. This practice’s work is overwhelmingly in the opposite direction — we spend most of our clinical effort reducing opioid burden in patients who arrive on high doses, and we have written about why that burden stops working in opioid bankruptcy and why tapering is a bridge, not a destination.

What early treatment means in CRPS is:

• Sympathetic blocks — targeted injections that interrupt the sympathetic contribution to the pain, used both diagnostically and therapeutically, and most useful early.
• Ketamine, where the presentation warrants it, as an NMDA-receptor approach to central sensitization. Route matters considerably; we set out the evidence by route in ketamine for a limb that burns after the injury healed.
• Graded motor imagery and desensitization, sequenced after pain is controlled enough for movement to be tolerable.
• Neuromodulation for established cases that have not responded to less invasive options.
• Addressing the metabolic terrain, because inflammation is not only neurological. See hyperinsulinemia and chronic pain.

Whether a short, carefully bounded course of analgesia has a place while those interventions take effect is a clinical judgement made patient by patient, and it is genuinely contested in the field. It is not a policy that can be set in advance by either enthusiasm or fear.

What the delay actually cost

Joseph lost the ability to climb, then the job, then the income. Medical bills accumulated against no earnings. The marriage did not survive it. He drank, because when the medical system declines to address pain, people find their own means, and the ones they find are worse.

None of that appears in a chart as a complication of CRPS. All of it followed from the decision not to treat.

By the time he reached us, the question was no longer how to prevent central sensitization. It was how much function could be recovered from an established case — a materially harder problem, with a worse expected outcome, in a patient who had lost the resources to pursue it.

Individual results vary, and Joseph’s course is one patient’s, not a prediction. What generalizes is the sequence: pain that is dismissed early becomes pain that is expensive to treat late.

Frequently asked questions

How quickly does CRPS need to be treated?

Sooner is materially better. The window in which the condition responds well is measured in months, not years, because central sensitization becomes more established the longer the pain signal runs. If a limb hurts disproportionately after an injury has healed, that is the point to seek evaluation — see how CRPS is diagnosed.

Are anti-inflammatories useless for CRPS?

Not useless, but not sufficient. CRPS pain is substantially neuropathic and centrally maintained, and NSAIDs act mainly on peripheral inflammation. They carry real cardiovascular, kidney and gastrointestinal risk with long-term use. Do not start, stop, or change any medication without consulting your physician.

Is physical therapy harmful in CRPS?

No — but sequence matters. Early and graded, it is valuable. Imposed on a severely sensitized limb without pain control first, it commonly backfires. The therapy should follow enough pain control to make movement tolerable.

Does treating pain require opioids?

No. The great majority of what we do for CRPS is interventional and metabolic, and much of our practice is spent reducing opioid burden rather than adding to it. See why opioids stop working.

Where can I be evaluated?

Padda Institute, 4477 Woodson Rd, Suite 100, St. Louis, MO 63134, serving the St. Louis region across Missouri and Illinois. Call (314) 481-5000 or text (314) 886-5902.

Key takeaways

• CRPS treated early responds better; delay allows central sensitization to become established.
• NSAIDs and unsequenced physical therapy are not a treatment plan for CRPS.
• Untreated pain is an exposure in its own right, with observed associations to later cognitive decline.
• Early treatment here means sympathetic blocks, ketamine where indicated, graded rehabilitation and metabolic work — not opioids.
• The costs that end a career and a marriage are not recorded as complications, but they follow from the same delay.

Medically reviewed by Gurpreet Singh Padda, MD, MBA, MHP — Board Certified in Anesthesiology, Pain Medicine, Interventional Pain Management, Addiction Medicine, and Obesity Medicine. Last reviewed August 2026.

This article is educational and is not a substitute for evaluation, diagnosis, or treatment by a physician. Individual results vary. Do not start, stop, or change any medication without consulting your physician.

Dr. Gurpreet Singh Padda, MD, MBA, MHP