Complex Regional Pain Syndrome (CRPS) and LDN

Living with Complex Regional Pain Syndrome (CRPS) can feel overwhelming. This long-lasting pain condition often starts after an injury or surgery and can make even the most minor tasks feel impossible. CRPS is tricky to treat, and many people spend years searching for something that genuinely helps. Recently, Low Dose Naltrexone (LDN) has started to gain attention as a new option for managing CRPS, especially when other treatments haven’t worked.

In this blog, we’ll explain what CRPS is, why inflammation is so important, and how LDN might offer hope for those struggling with daily pain. Whether you’re a patient, a carer, or just curious, you’ll find clear answers and practical advice here.

Five key takeaways

• CRPS is a long-lasting pain condition that usually affects the arms or legs, often starting after an injury or surgery.
• Inflammation plays a major role in CRPS, keeping nerves sensitive and causing ongoing pain, even after the original injury has healed.
• Low Dose Naltrexone (LDN) is a promising new option for people with CRPS, as it may help calm inflammation and support pain relief when other treatments haven’t worked.
• Real-life cases show that LDN can help some people with CRPS reduce their pain, need fewer strong painkillers, and even regain daily function.
• CRPS treatment is complex and often needs a mix of approaches, including physical therapy, medications, and sometimes nerve blocks or spinal cord stimulation.

What is Complex Regional Pain Syndrome (CRPS)?

Complex Regional Pain Syndrome (CRPS) is a long-lasting pain condition that usually affects the arms or legs [1]. It often starts after an injury or surgery and is much more common in women [2]. There are two types [3]:

• CRPS-I: No confirmed nerve injury
• CRPS-II: There is a known nerve injury

People with CRPS may feel pain from things that wouldn’t usually hurt (like a light touch), and their skin might be extra sensitive [1]. Previous injuries and traumas are the most common risk factors for developing CRPS [4]. Other risk factors include fibromyalgia [5], rheumatoid arthritis [6], and sometimes a history of depression or stress [7].

What’s happening in the body?

CRPS is complicated, but inflammation plays a big part [8]. After an injury, the body’s immune system can go into overdrive. Instead of calming down, it keeps sending out chemicals called cytokines that cause redness, swelling, warmth, and pain. This ongoing inflammation can make nerves more sensitive and keep the pain going, even after the original injury has healed [1].

In CRPS, the nerves that sense pain (especially C-fibres) become very active [1]. This leads to the release of more inflammatory chemicals, which only adds to the pain and swelling. Over time, the body’s defences can even start to attack the nerves, making the problem worse.

Other things that can play a role:

• The body’s automatic (autonomic) nervous system can get out of balance, causing changes in skin colour, sweating, and temperature [9].
• Genetics and psychological factors (like depression or PTSD) might also make someone more likely to get CRPS [1].

How is CRPS treated?

Treating CRPS can be tricky. The main goal is to reduce inflammation, manage pain, and keep the affected limb moving. Treatments can include:

• Physical therapy and mirror therapy [1],
• Medications like steroids, bisphosphonates, gabapentin, and ketamine [1],
• Antioxidants, such as vitamin C [10].
• Newer options like low-dose naltrexone (LDN), which may help calm inflammation in the nerves [11].
• Interventions like nerve blocks or spinal cord stimulation in complex cases [12].

CRPS in summary:

CRPS is a painful condition where inflammation in the nerves and tissues plays a significant role. It’s a complex problem, but understanding the role of inflammation is helping doctors find better ways to treat it and improve the quality of life for people affected by CRPS.

How does LDN fit into the picture for Complex Regional Pain Syndrome (CRPS)?

Low Dose Naltrexone (LDN) is a medicine that’s being explored as a new way to help people with CRPS. It’s usually taken in very small doses (1–5mg). While LDN isn’t officially approved for CRPS, some doctors prescribe it “off-label” because it may help calm the immune system and reduce inflammation, both of which are thought to be involved in CRPS [11].

What is Low Dose Naltrexone (LDN)?

Low-dose naltrexone is a medication that’s getting a lot of attention for its possible benefits in long-term health problems like chronic pain and immune system issues, including CRPS.

Where did LDN come from?

Naltrexone was first made to help people stop using opioid drugs or alcohol. At high doses (about 50mg or more), it works by completely blocking the brain’s opioid receptors [13].

These receptors are like locks for your body’s natural painkillers (endorphins) and drugs like morphine. When someone takes a high dose, these locks are blocked all day, so opioid drugs can’t work, and people lose the “reward” feeling from these substances.

What’s different about Low Dose Naltrexone?

LDN is the same medicine, but in much smaller doses—usually between 1mg and 4.5mg. At this low dose, it doesn’t block the receptors all day. Instead, it only blocks them for a short time [14].

How does LDN work in the body?

When you take low-dose naltrexone, it briefly blocks your body’s natural painkillers (endorphins) from fitting into their “locks.” Your body quickly notices and makes more endorphins to get around the block. When the LDN wears off, you have extra endorphins in your system [14]. These natural chemicals help with pain relief, can boost your mood, and may help calm down overactive immune responses [14].

In simple terms:

• High-dose naltrexone: Blocks opioid receptors all day, used to treat addiction.
• Low Dose Naltrexone (LDN): Briefly blocks receptors, then lets them go, which encourages your body to make more of its own natural painkillers. Used “off-label” for chronic pain, immune problems, and CRPS.

How does LDN help with CRPS?

Low-dose naltrexone gently “nudges” both your immune and nervous systems. At low doses, it can calm special brain cells and help reduce inflammation in the nerves [11]. It also helps your body make more endorphins, which can ease pain and support your overall well-being.

Complex Regional Pain Syndrome (CRPS) and LDN: Real-life Results

CRPS is a tough pain condition to treat, but some people have seen significant improvements with Low Dose Naltrexone (LDN) [11], [15].

In two reported cases, patients had CRPS for over three years, making even simple things like walking very hard. After just two months of taking LDN, both needed much less ketamine for pain and saw a massive improvement in their symptoms [11].

One person was able to stop using a walking cane, and the other had foot surgery without their pain getting worse—eventually, that person’s CRPS went away completely [11]. This is important because surgery and injuries can often make CRPS worse, but that didn’t happen here.

Another case involved someone with several health problems, including Ehlers-Danlos syndrome, gut issues, sleep apnoea, and CRPS in one leg after undergoing cardiac catheterisation [15]. This person had tried many treatments for eight years without success. When LDN was added to their care, their CRPS finally went into remission [15].

In short, while CRPS is very hard to manage, LDN has helped some people get their symptoms under control—even when other treatments haven’t worked [11], [15].  

Summary

Complex Regional Pain Syndrome (CRPS) is a challenging pain condition that can develop after injuries or surgery, most often affecting the arms or legs. It’s more common in women and can be linked to other health problems like fibromyalgia or rheumatoid arthritis. The main driver of CRPS is inflammation, which keeps nerves sensitive and causes pain, swelling, and skin changes.

Treating CRPS usually involves a combination of physical therapy, medications, and sometimes more advanced options. Low Dose Naltrexone (LDN) is a newer, “off-label” treatment that may help by calming inflammation and boosting the body’s natural painkillers.

Real-life stories show that LDN can make a big difference for some people, even when other treatments haven’t worked. If you or someone you know is struggling with CRPS, it’s worth discussing all the options, including LDN, with a knowledgeable healthcare professional, or contact us for FREE LDN consultation.

Frequently Asked Questions (FAQs)

What is CRPS?

CRPS stands for Complex Regional Pain Syndrome. It’s a long-term pain condition, usually affecting the arms or legs, that often starts after an injury or surgery [1].

What are the main symptoms of CRPS?

Symptoms include ongoing pain (even from light touch), swelling, changes in skin colour or temperature, and extra sensitivity in the affected area [1].

How is CRPS usually treated?

Treatment usually includes physical therapy, medications (like steroids, gabapentin, and vitamin C), and sometimes nerve blocks or spinal cord stimulation. Treatment is often tailored to each person [1].

What is Low Dose Naltrexone (LDN), and how does it help?

LDN is a medicine originally used for addiction in higher doses, but in small doses, it may help calm the immune system and reduce inflammation in people with CRPS. Some people have seen big improvements with LDN, even after other treatments failed [11],[14], [15].

Is LDN safe for everyone with CRPS?

LDN is generally well-tolerated, but as with any medicine, it should only be started under the care of a healthcare professional who understands your health history [16].

Can LDN cure CRPS?

LDN isn’t a cure, but it may help reduce symptoms and improve quality of life for some people with CRPS, especially when other treatments haven’t worked [11], [15].

References:

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