Detailed guides to painful problems, treatments & more

What Works for Pain?

A roundup of all the most effective treatments and rehab strategies for common kinds and causes of chronic pain

Paul Ingraham • 40m read

Chronic pain is hard to treat — as profound an understatement as I can imagine. Treatments are notoriously underwhelming.1 “What works?” is one of the most unanswerable questions in all of medicine because “it depends,” always, on so many things. Pain is the king of It Depends.

Like cancer, pain is not one thing. It has literally thousands of possible causes. Nothing can possibly work for everyone or in every situation, and perversely even short-term success can lead to long-term failure.2 Pain is also so integrated into our “wiring” and identity that it is nearly impossible to suppress it without numbing the person (or critical subsystems) at the same time — which is why the only total analgesia is anaesthesia.3

Removing a definite cause of the pain is the ultimate treatment, like Androcles removing the thorn from a lion’s paw. Unfortunately, the metaphor of the thorn only fits some cases of chronic pain. It is startling and terrible how often no “thorn” can be found — and how many more can be found but not removed. And strange how many things look like thorns but aren’t actually the problem, and cause long wild goose chases. It’s a thorny problem!

What then for the rest of us?

The problem is immense. As of the early 21st Century, what are the best solutions for the most common problems? What is the most evidence-based and plausible? What actually works in at least some specific way, for well-defined groups of suffering people?

Anything? 😬

Yes, a few things do work well enough for that.

Since 2001, I have been debunking the pseudoscience and quackery that dominates the options for pain patients. I have been very “negative.” Since 2015, I have ironically been a chronic pain patient myself, seeking answers as desperately as any of my readers over the years. This page is a long overdue optimistic collection of what definitely works for pain.

It’s not a long enough list, obviously — especially because it excludes many experimental therapies and speculative strategies that are genuinely “worth a shot” due to their lower costs and risks and somewhat higher plausibility (see Pain & Injury Survival Tips). This article is not about what might work for a few people, it’s about what definitely works for quite a few people.

But never everyone, and always with caveats.

It’s a myth that “nothing works” — despite the difficulties, relieving pain is probably easier than coping with it

The idea that nothing works for pain seems extreme, but some professionals seem to have embraced it so completely that they have “given up” on treating pain, and shift the focus to helping people with the fallout from pain: disability and suffering. The idea is that this is easier than actually treating pain.

Is it really wiser to try to treat disability and suffering rather than pain? Does it help people more? It sounds crazy to most patients, but is it actually just pragmatic, the “art of the possible”?

Saragiotto et al pooled a lot of data and reported that pain is actually the outcome most affected by treatment attempts.4 Relieving disability and suffering is not obviously easier, and in fact it is probably harder — especially if pain remains!

The evidence suggests the obvious: relieving pain is the shortest path to relieving disability and suffering. That doesn’t mean it’s easy, and it doesn’t mean it isn’t also worth trying to relieve disability and suffering (and good luck trying to treat one without the other in any case, which would be like trying to flip one side of a coin). But pain relief should still be the focus, if for no other reason than it’s what patients want, and that matters (a lot). Giving the goal of pain relief short shrift can seriously piss patients off.5

Modern thorn removal: not “what works” exactly, but the greatest source of hope

That is, the power to identify and remove obscure causes of persistent pain — “thorns” — that we couldn’t find and remove before.

Nothing beats actually identifying a treatable problem that is the unambiguous cause of the pain. My favourite simple example is my friend with intractable back pain who was finally cured by the removal of a small tumour from a nerve root — after years of wrong theories, failed therapy, and escalating misery. One day his nightmare was just over, because the tumour was identified by the right expert looking in the right place in the right way (the right kind of MRI).

“Well, there’s your problem.”

This is the single best thing that modern medicine has to offer to anyone with unexplained chronic pain: a deep catalogue of hard-to-diagnose pathologies that cause pain, and the power to actually diagnose them (despite the difficulties). Not all such things can be treated, of course, but many can. The search for such a diagnosis remains the single best hope for many chronic pain patients. The failure to find a thorn — a persistent source of nociception (noxious stimuli) — even after many years, does not mean it isn’t there.

This isn’t a “treatment” per se, and it barely even counts as a strategy. You can’t even go to one doctor to hunt a tricky diagnosis, because there is no such thing as a specialist in all possible causes of pain. And medicine clearly still has more to learn. But! There is much more relevant knowledge out there today than there was a hundred or fifty or even twenty years ago. This is a legitimate cause for hope, the single best good news I can think of.

To help you get started on the search, I have compiled a fairly large list of diverse examples of surprising causes of pain.

Now for some more specific things that work…

Opioids work (for some things, and with major risks)

Opioids are the “nuclear option” in pharmacological analgesia — and perhaps the ultimate perfect example of something that works especially well in a specific context only. Most notably, they are ideal for dying people, because their grim side effects cannot threaten people who won’t exist in a few weeks or months. The existence of this option is one of the least appreciated greatest hits of modern medicine, arguably as big a deal as anaesthesia, vaccination, antibiotics, and so on. For the dying, it’s a really big deal.

For everyone else? It’s more complicated, problematic, and fiercely controversial. But opioids are also extremely effective for many not-dying-yet chronic pain patients, for whom the risks are very much the lesser of evils. The demonization of opioids has disastrously limited access for many patients who truly can benefit from them, and also stigmatized them.

Obviously there’s a ton of bad news about opioids — not just the addiction problem, but the disturbing truth that they aren’t as potent as we’d like to think. They can be surprisingly ineffective for some people (genetics!) and for many kinds of chronic pain.

Over-the-counter analgesics work (not amazingly well, but reliably for a lot of things)

For every chronic pain patient who sneers at this option — and they do sneer! — there are two more who can’t imagine life without it. For instance, my own father has had impressively good results treating rheumatoid arthritis with naproxen (though not, of course, without side effects). The OTC pain-killers absolutely can work quite well for many conditions — and in some cases they are even amazingly safe (most notably acetaminophen within recommended dosages).

The over-the-counter analgesics mostly work by inhibiting various aspects of inflammatory signalling, in contrast to the narcotics which alter perception of pain regardless of how it’s being produced. So they can only do so much… but they definitely do something.

Menstrual cramping is one of worst pain plagues suffered by humans — and it can often be treated surprisingly effectively by a specific type of pain-killer, the non-steroidal anti-inflammatory drugs (like ibuprofen and aspirin).6 It’s a great example of something truly effective for a very specific context, but also an extremely common one. This is not to say that it always helps — there are definitely cases — but it’s a revelation for many women to learn that the NSAIDs specifically will often succeed where other common pain killers definitely fail.

Another modern standout is topical diclofenac, one of the NSAIDs. Absorbing diclofenac through the GI tract is madness, rife with serious side effects. But in tiny doses through the skin, right where it’s needed? •chef’s kiss• It is a truly good option for many, many kinds of pain.

Counterstimulation works (a little bit for a lot of people)

Counterstimulation is a basic neurological mechanism for minor temporary pain relief, a sensory “distraction” from pain. It’s not a potent thing, but it is a real thing, and it is probably responsible for the modest efficacy of many, many pain treatments that supposedly work some other way, but actually work this way.

You could call it another tool for the pain treatment toolbox, but it’s not an impressive tool — maybe just like a small screwdriver or a tack hammer.

It’s also why many kinds of chronic pain can and probably should be routinely treated with all manner of minor sensory pleasures and self-grooming: routinely, cheaply, and slightly fighting pain with other sensations, from the “spicyness” of a hot lotion, to the luxury of hot tub jets, to squirming around on a foam roller.

Like the OTC pain killers, counterstimulation is rarely going to work any miracles — but it will always be at least a little bit useful for many people.

It is probably the reason that massage and other manual therapies are perennially popular — which is both good news and bad. The good news is that it’s part of a legitimate explanation for why we like those treatments. The bad news is that it props up many bogus narratives about how they work, which in turn fuels a staggering amount of false hope. I explain this in more detail here:

Comic strip, 4 panels, all featuring two ancient soldiers standing up, and several more lying on the ground in front of them, seemingly dead. Panel one: one live soldier asks, “How do we know if they’re actually dead or just pretending?” Second panel, the other soldier shouts: “I have chronic pain!” Third panel: four of the seemingly dead soldiers speak up, saying “Yoga!” “CBD!” “Lasers!” “Meditation!” In the fourth panel, the two live soldiers proceed to finish off the soldiers who revealed themselves as just pretending.

People just cannot resist suggesting their favourite remedies to people who say they are in pain. But nearly everything casually suggested is a clean miss for most patients with serious pain, if not all of them.

Exercise and fitness work (if you don’t overdo it, and for some people it’s tragically easy to overdo it)

It has been said that exercise is the closest thing there is to a miracle cure. What makes exercise such a wonder drug? For those who can do it, exercise provides both short-term pain relief and long-term, widespread health benefits that are both inherently analgesic and also support recovery from most injuries and many ailments. It even seems to help injured brains.7

It’s also nearly infallible, if you are persistent and sensible about not overdoing it.

The big “but” is that quite a few people with chronic pain are also exercise intolerant, and simply cannot exercise enough to reap the rewards. Fibromyalgia patients are highly variable in their response to exercise, ranging from “very helpful if cautious” to “backfires almost every time,” probably because they have a wide variety of underlying conditions driving similar-ish symptoms.

But for many, many people with chronic pain, exercise works because it is biologically “normalizing,” pushing complex systems to work the way they are supposed to work. Biology is all about clever homeostatic mechanisms that nudge tissue state back to average. Those systems all rely on negative feedback loops based on molecular signalling (hormonal, neurological, etc), and exercise produces a lot of raw “data” to feed into those loops. Exercise cannot normalize everything. But it does stimulate an incredible array of adaptive and homeostatic mechanisms — way more than any medicine, supplement, or superfood.

Increased fitness is probably the ultimate way to reduce systemic vulnerability to pain, mostly through the mechanism of reduced inflammation. Poor fitness correlates strongly with an array of disease risks which are mostly all about chronic, subtle systemic inflammation, and fitness is the antidote.

Progressive loading works (where the problem is tissue overload)

A lot of chronic pain is caused by failure of recovery from tissue overload — repetitive strain injury — usually because the source of tissue stress is never reduced enough. Basically, people just keep re-injuring themselves: poor “load management.”

The body can recover from almost anything if you give damaged tissue an adequate rest and then slowly give it more functional challenges, starting very easy and working your way back up (“progressive training”). Baby steps, wisely executed, rarely fail to take a person back to normal. When this strategy does fail, it’s usually because the problem wasn’t tissue overload to begin with … which does happen, because an underlying biological vulnerability can easily create the appearance of a conventional injury. This is a one of the all-time best examples of how nothing works for everyone: progressive rehab is a fantastic principle where applicable.

This is a basic principle of rehab that has no direct evidence, because the strategy is too complex to meaningfully test, but it is supported by powerful “circumstantial” evidence and high biological plausibility. In my opinion, it doesn’t get enough credit because of a strong culture of excessively aggressive rehab strategies that routinely doesn’t allow enough recovery time to be successful. When done methodically, and carefully avoiding overload, it’s highly effective. But there is no citation for that: it’s a modest and logical extrapolation from the extremely powerful evidence that exercise in just-right doses is a powerful adaptive stimulus.

Drugs for neuropathy work (for a very lucky few)

Neuropathy is a malfunction of the nervous system itself: pain caused by dysfunction of the pain system. Many drugs that tinker with neurological function, often suppressing it in some way, are helpful for some of these patients. However, it generally takes rather a lot of experimentation to find the right drug — something that works well enough, with tolerable side effects.

Arguably, we do not have effective enough drug therapy for neuropathy to put it on any list of “what works for pain,” and some of the drugs generally touted as efficacious for neuropathy probably don’t deserve their reputation. However, it’s equally clear that drug therapy does work well enough for some patients that the world would be a much more desperate place without it. It’s far from a silver bullet for neuropathy, but many people have been saved by just the right drug.

Neurostimulation with implants works, especially spinal cord stimulation (for those that qualify)

The modern era of electrical therapy began when deep brain stimulation was introduced in 1987, and it has been steadily improving since then, thanks to better surgical techniques and a greater understanding of the neurology of pain. In just the last decade, I think it has improved enough to qualify for this list.

There are many types of neurostimulation, but I’m referring mainly to spinal cord stimulation (SCS). Peripheral nerve stimulation is much too mediocre, and brain stimulation — while extremely promising — is not quite ready for prime time.

Any invasive treatment has major risks, of course, and it’s generally only a good option for specific kinds of patient with particularly great need. But SCS can be almost miraculous for many patients. Interestingly, it’s largely based on counterstimulation (discussed above) — but the “potency” is dramatically greater than you can get from any superficial stimulation.

Actually using best practices in musculoskeletal medicine works

Pain is too complex and multifactorial for one-size-fits-all solutions, which makes it very difficult to say “what works.” But if many factors contribute to pain, then many factors are probably involved in treatment, complex care for a complex problem: medicine that includes many best practices, wisely and skilfully applied.

And what does that look like, pray tell?

It’s not a mystery. A 2019 paper distilled several key best practices in musculoskeletal medicine from eleven recent, high quality, English clinical practice guidelines.9 See that footnote for the formal language. Here is a translation of those best practices into plain English:

And saving the best for last, the one that is the most challenging to so many professionals, and so different from what most patients actually get:

This isn’t a perfect list, of course (and exactly how it falls short is a much longer conversation). But it certainly does describe a kind of care that is miles better than what most patients are actually getting. Many of these best practices are bizarrely neglected by — or even at odds with — the common beliefs and practices of healthcare professionals who should know better.10

If every patient with a stubborn painful problem got care that ticked all of these boxes, I think a lot more of those problems would get meaningfully helped. There’s no citation for that, of course: it’s impossible to standardize complex care (almost a paradox, really). But each individual component is to some extent based on good science, and I think they undoubtedly add up to something that “works.”

Treating insomnia works (for some people with insomnia)

Sleep deprivation plays a major role in some cases of chronic pain, and makes a bad situation worse for many others. There are a lot of systemic stresses that contribute to vulnerability to pain, but sleep deprivation is one of the most obvious common ones that can often be solved or significantly mitigated. Although insomnia has as many causes as chronic pain, we understand many of them quite well, and several types can now be easily treated or even outright cured.

Even total recovery from insomnia isn't going to actually cure much chronic pain — but it’s indisputably an upgrade, a complex and indirect but reliable way to reduce the impact of chronic pain for some patients.

Pain relief in the future

There are two areas of major promise in the future of exciting, high-tech pain medicine:

But the greatest potential in health care is always with the boring basics, and that applies as much to pain as any other medical issue. The “root causes” of most chronic pain go deep: poor health and inadequate care, which are in turn driven by poverty, social injustice, and dysfunctional institutions and governance. Improving these things is not a “pain treatment,” per se, but it’s as important to pain as sanitation is to public health. Systemic changes have by far the greatest potential to relieve pain… and, of course, they are also the least likely to actually happen. Because, as basic as these things are, they can only be produced by a more advanced and better-organized society: progress, the hardest thing there is.

Notable exclusions

Some things will get added to the list above in time. But not many, and not these: several exclusions that many people will ask about if I don’t mention them.

There are, of course, many many more that I could mention. But these are the ones that people are most likely to ask about if I don’t mention them.

Is there something you think should have made the cut, but you don’t see anywhere on this page? Feel free to ask.

What’s new in this article?

Four updates have been logged for this article since publication (Jun 30th, 2021). All PainScience.com updates are logged to show a long term commitment to quality, accuracy, and currency. more Like good footnotes, update logging sets PainScience.com apart from most other health websites and blogs. It’s fine print, but important fine print, in the same spirit of transparency as the editing history available for Wikipedia pages.

I log any change to articles that might be of interest to a keen reader. Complete update logging started in 2016. Prior to that, I only logged major updates for the most popular and controversial articles.

See the What’s New? page for updates to all recent site updates.

Mar 5, 2022 — New sidebar: “The price of honesty and humility.”

February — Added some comic relief: the dead-or-pretending meme, the you-keep-using-that-word meme, plus a sidebar, “What people think I do for a living….” (which is fun, but also goes a little deeper).

February — New section: “Actually using best practices in musculoskeletal medicine,” plus a bunch of editing throughout the article. Almost ready for prime time!

2021 — New section: “Pain relief in the future.”

2021 — Publication.

Notes

  1. Pain medicine has been slowly choking to death on “evidence” that shows minor transient benefits to virtually all treatments for most patients. For instance, it’s a given these days that most manual and passive therapies can be shown to have statistically significant but clinically trivial effects, modest and temporary at best.

    In most cases, even that much is probably just a research artifact, wishful thinking powered by methodological and statistical jiggery pokery (e.g. p-hacking).

    In the remainder, it’s probably attributable to non-specific effects that weren't adequately controlled for.

    And so we have endless “promising” results that rarely, if ever, amount to anything more — if they are even legit in the first place, which they often aren’t, because there are so many ways to warp a little study so that it confirms a bias (see Cuijpers). Literally no manual or passive therapy — like massage, spinal traction, ultrasound, or cartilage debridement — has ever been shown to have an unambiguously impressive effect on rehabilitation. See Cook.

    Even some of the most highly regarded champions of rehab fail to stand up to scrutiny. I spent an hour re-reviewing the research on heel drops for Achilles tendinitis in the hopes of including it in this article as a fine example of something that works, because it is so widely embraced as an effective intervention. But it is actually not that impressive. It does not clearly “work.”

    And so it goes, all the way down virtually the entire mighty list of options for virtually everything that hurts.

  2. I am referring specifically to the paradox of downregulation of opiate receptors. Any artificial stimulation of the firing of inhibitory nerve pathways — one of the most potent ways to relieve pain — also desensitizes those pathways, crippling them for your future self.
  3. The pain system is necessary part of us, like a vital organ that’s everywhere. It’s one of the main reasons we have a nervous system in the first place. Half our biochemistry is devoted to dealing with threats, and most components have other critical jobs. Anything potent enough to really shut pain up is also going to shut you down: anaesthesia, opioids, steroids, tetrahydrocannabinol, Botox … everything that is to some degree useful also tends to have a substantial price tag, usually the loss of some kind of functions. And so pain treatment is always going to be some kind of compromise. When the reward is total pain relief, the cost is the temporary but total obliteration of consciousness by anaesthesia.

  4. Saragiotto BT, Maher CG, Traeger AC, Li Q, McAuley JH. Dispelling the myth that chronic pain is unresponsive to treatment. Br J Sports Med. 2017 Jul;51(13):986–988. PubMed #27797740 ❐

    “The view that pain is not the best measure of treatment success for chronic pain is not evidence-based. The assumption that behavioural or psychological therapies mainly reduce disability but not pain is not consistent with the data from Cochrane reviews on chronic LBP. Pain intensity should be measured in chronic pain research and clinical practice. Considering pain intensity to be the wrong metric for chronic pain hampers treatment selection and does our patients a great disservice.

  5. Consider this quote:

    “Our duty to patients with chronic pain is not to reduce pain intensity, but to improve their quality of life.”

    That sentiment makes a poor impression on patients. One of my most popular tweets expressed a little outrage about it:

    “Putting my patient hat on here. Speaking as a chronic pain patient, not even trying to look at this from a clinical perspective… I want the intensity of my pain reduced. Just that. Pretty 🤬 sure THAT would ‘improve quality of life.’”

  6. Menstrual cramping is triggered by prostaglandin, a signalling molecule produced by the womb during menstruation, and also an important part of inflammation. NSAIDs inhibit the production of prostaglandin, which suppresses inflammation … and menstrual cramps specifically and especially. It’s a very specific biochemical effect, making the NSAIDs truly effective muscle relaxants for this one specific kind of muscle cramping. Other over-the-counter pain-killers, most notably acetaminophen, do not have this effect.
  7. Leddy JJ, Haider MN, Ellis M, Willer BS. Exercise is Medicine for Concussion. Curr Sports Med Rep. 2018 Aug;17(8):262–270. PubMed #30095546 ❐ PainSci #52267 ❐

    This is a positive review of moderate exercise as “medicine” for brain injury, concluding that it probably normalizes concussed brains, even in cases of persistent post-concussion syndrome.

  8. I am highly critical of “corrective” exercise — the alleged use of specific, technical exercises to “fix” allegedly clinically significant weakness and assymetries. See “The Corrective Exercise Trap”.

    And I even have awkward mixed feelings about progressive loading — we know that overloading is a risk factor for injury, especially spikes (see Soligard et al), and so it just seems to make sense that “managing” load would be an important part of both prevention and recovery. And that may be true in some ways. But there is also evidence that gives me clear cause for reasonable doubt that progressive loading actually “works” (Hopewell et al). No matter how much sense it makes, there is both an absence of evidence and some evidence of absence.

    I tried hard to find a single specific example of compelling evidence of efficacy for exercise as rehab for any common injury, just so that I could include it in this article. One of the best candidates is heel drops (eccentric contraction) for Achilles tendinitis, which is accepted as good evidence-based rehab by lots of pros. But I just don’t see it, and it did not make the cut. “There is no convincing clinical evidence to demonstrate that isolated eccentric loading exercise improves clinical outcomes more than other loading therapies” (Couppé et al). But “other loading therapies” (regular heel raises, concentric contraction instead of eccentric) produce no compelling results either. The whole reason eccentric is held in high regard is because it’s supposedly better than concentric!

  9. Lin I, Wiles L, Waller R, et al. What does best practice care for musculoskeletal pain look like? Eleven consistent recommendations from high-quality clinical practice guidelines: systematic review. Br J Sports Med. 2019. Here are the recommendations quoted verbatim:
    1. Care should be patient centred. This includes care that responds to the individual context of the patient, employees effective communication and uses shared decision-making processes.
    2. Screen patients to identify those with a higher likelihood of serious pathology/red flag conditions.
    3. Assess psychosocial factors.
    4. Radiological imaging is discouraged unless:
      1. Serious pathology is suspected.
      2. There has been an unsatisfactory response to conservative care or unexplained progression of signs and symptoms.
      3. It is likely to change management.
    5. Undertake a physical examination, which could include neurological screening tests, assessment of mobility and/or muscle strength.
    6. Patient progress should be evaluated including the use of outcome measures.
    7. Provide patients with education, information about their condition and management options.
    8. Provide management addressing physical activity and or exercise.
    9. Apply manual therapy only as an adjunct to other evidence based treatments.
    10. Unless specifically indicated (e.g. red flag condition), offer evidence-informed non-surgical care prior to surgery.
    11. Facilitate continuation or resumption of work.
  10. For instance, the importance of psychosocial factors is either entirely neglected or hotly contested by many; or it is paid lip service but given short shrift in practice. There is an immense gap between theory and practice in musculoskeletal medicine, with vast numbers of professionals perpetually indulging in pet theories of pain and wildly overestimating the value of passive therapies — the power of gadgets, tools, and hands — while underestimating and neglecting everything else.
  11. Zhang Q, Hu S, Talay R, et al. A prototype closed-loop brain-machine interface for the study and treatment of pain. Nat Biomed Eng. 2021 Jun. PubMed #34155354 ❐

    This study advances the science of brain-machine interfaces with a test of an implanted computer chip in rat brains, designed to treat chronic pain. The chip reads the rat’s minds: it detects patterns of brain activity in the cingulate gyrus that are consistent with pain, and then stimulates part of the frontal lobe to mute pain: specifically, to “exert top-down nociceptive regulation.” Obviously this is very invasive, and even if it works there’s a risk of adaptation and dependence, and human applications are many years off.

    Doing this for humans is probably still many years away. But if it works? It’s extremely precise, responding in real-time, only working when there’s pain to treat — completely unlike the continuous, always-zapping approach that has dominated the field so far.

    And it really did work amazingly well. The treated rats withdrew from painful stimuli about 40% slower, and greatly preferred spending time in a chamber where the implant was functional to one where it wasn’t. These were strong results, and a very promising demonstration of the principle.

    This kind of approach is likely to improve as we continue to improve brain-machine interface technology, and knowledge of brain circuity gets more precise.

    See neurologist Dr. Steve Novella’s more detailed explanation of this experiment.

  12. Science fiction is full of cautionary tales about a brain interface tech that is still decades away (if ever). Yes, you might get used as a battery by our robot overlords. Meanwhile, back in the early to mid 21st Century…

    The obvious problem with a technique like this is that it’s about as invasive as invasive can get — it’s a brain implant. There are going to be complications.

    Technological glitches aren’t out of the question either. This is not a simple device. “Have you tried rebooting it?” is not what patients want to hear when they call tech support for their brain implant.

  13. Here’s a less obvious and more interesting concern: this could cause adaptation and dependence just like opioids. Any time you overstimulate an inhibitory neurological function, there’s a chance that it will get a bit numbed to the input… and no one wants a pain inhibition system that isn’t working at full power. Understatement.

    We know this phenomenon extremely well from opioid dependence, but the inexorable logic of “downregulation” applies to anything that tinkers with nerves to kill pain. Pick a pathway that inhibits pain, any pathway, give it a boost with some kind of artificial stimulation, and gosh darn it if it doesn’t start downregulating and become less responsive to natural stimulation… et voila, you become either dependent on the artificial stimulation, or seriously sensitized without it.

    But “it’s complicated,” of course. This will just have to be studied over time to find out if that happens.