Acetyl-L-Carnitine: Just How Useful Is It For Neuropathy Problems?

Today's post from salubrainous.com (see link below) follows on from yesterday's post about alpha lipoic acid and provides a detailed article about the supplementary benefits of Acetyl-L-Carnitine for nerve damage problems. You may wonder why I'm concentrating on these two c-enzymes but these are among the most commonly advised supplements for neuropathy and while not everybody will see benefits from taking them, they are generally regarded as safe and are supported by the medical profession too. The point is that if you are searching for supplements that may help reduce your symptoms and maybe provide other benefits for your health, these two are a good place to start but be warned...they're not cheap and you need to take them for several months before judging whether they genuinely benefit you or not. That's why articles such as this one are so valuable because you can read the information, discuss it with your doctor or neurologist and make your own mind up. One last point; it's important to buy the best quality you can afford and get advice about the best dosage.

n.b. The products shown on this page are suggestions by the author only - you need to research the best buys for yourself


4 Evidence-Based Benefits of Acetyl-L-Carnitine For Neuropathy
December 4, 2017 Shruti Baikerikar




Name: Acetyl-L-carnitine, acetylcarnitine, acetyl-carnitine, l-acetylcarnitine, acetyl levocarnitine, N-acetyl-l-carnitine, ALC, ALCAR
Number of scientific references: 41

Level of Evidence: Level III What is this?

Note: Acetyl-L-carnitine is proven to improve nerve function and reduce neuropathic pain. It supports nerve regeneration. Studies in humans have found it beneficial for treating diabetic and HIV associated neuropathy.

Carnitine is an amino acid present in our body. It is involved in cellular energy and is present in high concentrations in skeletal and heart muscle for better utilisation of fatty acid as fuel. Inside the mitochondria (energy-producing units of the cell), carnitine is converted to acetyl-l-carnitine.

Acetyl-l-carnitine (ALC) is synthesised in mammalian kidney, liver and brain. Just like carnitine, it plays an important role in mitochondrial function.

Acetyl-l-carnitine is structurally similar to acetylcholine (a neurotransmitter of the cholinergic system that has many functions such as muscle contraction, fight or flight response and memory retention). It is a precursor of acetylcholine and mimics some of its functions.

This link with the brain chemicals makes acetylcarnitine, a potential therapeutic agent for brain and nervous system disorders. It has been used for treating Alzheimer’s, depression, chronic fatigue syndrome, brain injury and cognitive impairment.

It has also been used clinically for treating heart and metabolic health-related conditions.

Neuropathic pain is a disabling complication of various neurological disorders and occurs as a result of nerve injury. Glutamate is a neurotransmitter that is significantly involved in pain transmission including neuropathic pain. Glutamate receptors are proteins that bind to glutamate for supporting its function.

These receptors (specifically metabotropic glutamate receptors mGluR Group II and III) when activated relieve neuropathic and inflammatory pain. Acetyl-l- carnitine activates with these glutamate receptors to relieve neuropathic pain.

Acetyl-l-carnitine helps in peripheral neuropathy by relieving nerve pain and supporting nerve regeneration. It protects from neurotoxicity and restores nerve function.
Suggested Acetyl-L-Carnitine Supplements For Peripheral Neuropathy

Please consult a health practitioner before taking any health supplement.

Here are a few suggested acetyl-L-carnitine supplements. ALCAR goes well with ALA; you can check the alpha lipoic acid supplements suggested for peripheral neuropathy.

You may consider taking a supplement that combines Alpha Lipoic Acid and Acetyl-L-Carnitine but ensure you get adequate dosages of each.

Dosage: 1500-2000mg ALCAR

Doctor’s Best Acetyl-L-Carnitine with BioStint Carnitines Thorne Research Carnityl
Image Credit: Doctors Best

Image Credit: Thorne Research, Inc.
Contains 500mg ALCAR per veg capsule Contains 500mg ALCAR per veg capsule

4 Evidence-Based Benefits of Acetyl-L-Carnitine For Neuropathy

Acetyl-L-carnitine has been investigated in multiple human studies and pre-clinical studies to ascertain its benefits in neuropathy. Let’s go over a few of these studies.


Table of Contents [show]

1.Acetyl-L-carnitine is effective in relieving diabetic neuropathy
 
In 1996, Scarpini and his colleagues observed that patients with diabetic neuropathy and non-diabetic neuropathy had lower levels of carnitine and ALC in the nerves compared to normal individuals.

Insulin resistance in diabetes impairs fat and glucose metabolism; since carnitine and its derivatives are involved cellular fat metabolism, their supplementation helps mitigate such metabolic disturbances.

Findings of animal studies suggest that ALC supports nerve regeneration, rectifies nerve function and even prevents diabetic neuropathy.

In 2002, a group of Italian researchers examined the effect of acetylcarnitine on diabetic neuropathy patients. 333 patients participated in the study, and the study lasted for one year.

First, they were treated with acetylcarnitine or placebo injections (1000 mg for ten days) and then for the rest of the study duration they were given 2000mg ALC or placebo orally every day.

294 patients had impaired nerve function. Those treated with ALC experienced significant improvement in nerve function related parameters such as nerve conduction velocity within 12 months.

Pain reduced by 39% in those treated with ALC while those treated with placebo experienced only 8% reduction. The study confirmed that acetyl-l-carnitine is effective in reducing pain and improving nerve function and also safe as a long-term therapy for diabetic neuropathy.

A study published in Diabetes Care, 2005 reports that ALC (1000mg per day) is effective in reducing pain and improving nerve regeneration and sensory nerve function in diabetic neuropathy.

Evans et al. also suggest that ALC (2g per day) should be recommended at earlier stages of the disease to prevent progression and it can help in treatment as well as prevention of diabetic neuropathy.

B complex vitamins are essential for nerve health, and their supplementation relieves neuropathic symptoms. A recent study published in Journal of Diabetes Investigation, 2016 compared ALC with methylcobalamin (Vitamin B12) for treating diabetic neuropathy.

Patients were either treated with 500mg ALC thrice a day or 0.5mg methylcobalamin thrice a day for 24 weeks. Patients in both groups experienced a significant reduction in neuropathy symptom and disability, and both groups had improved nerve function. No significant side effects were observed.

Researchers concluded that acetyl-l-carnitine is as effective as methylcobalamin in improving symptoms as well as nerve function in diabetic neuropathy.

Cardiac autonomic neuropathy is a serious complication of diabetes where nerve fibres linked with the heart are damaged. Research suggests that acetylcarnitine may benefit in the treatment of cardiac autonomic neuropathy.


Quick Gist: Acetyl-l-carnitine at doses of 1-2g per day benefit in diabetic neuropathy by reducing neuropathic pain and improving nerve function. Research suggests that it may be as effective as Vitamin B12 in treating neuropathy.

2. It protects from neurotoxicity caused by anti-HIV medications

At high doses, HIV medications can turn out to be neurotoxic and contribute to peripheral neuropathy. Research suggests that HIV patients being treated with nucleoside analogues and diagnosed with neuropathy may have acetylcarnitine deficiency.

Oral 2000mg of ALC per day is reported to reduce pain within four weeks in HIV patients experiencing drug toxicity. A study published in HIV Clinical Trials, 2005 found that Acetyl-L-carnitine is safe for long-term treatment of HIV associated neuropathy and may reduce the possibility of discontinuing anti-viral medications.

Hart et al. conducted a study where HIV patients experiencing toxic antiretroviral neuropathy were treated with Acetyl-L- carnitine. The study lasted for 33 months, and the dose of acetylcarnitine was 1500mg twice a day.

Acetylcarnitine treatment improved symptoms and supported nerve regeneration in patients.

Intramuscular injection of acetylcarnitine (500mg twice a day) is found to relieve neuropathic pain in HIV patients with distal symmetrical polyneuropathy.


Quick Gist: Treatment with anti-viral drugs can have a dose-limiting toxicity and cause peripheral neuropathy. HIV patients may even have acetylcarnitine deficiency.

Supplementing with acetylcarnitine in such cases protects the nervous system from toxic effects of the drugs. It can support nerve regeneration and benefit in HIV associated neuropathy.

3.It is a neuroprotective and nerve regenerating agent

Acetyl-L-carnitine serves as a neuroprotective agent in case of peripheral neuropathy. It prevents activation of apoptotic pathways and prevents nerve cell death in neuropathy (apoptosis is cell death).

Neurotrophic factors are proteins that help in growth and maintenance of neurons. ALC normalises or increases the level of these proteins in neuropathy to relieve pain.

It reduces inflammatory damage to neurons by regulating levels of Brain Derived Neurotrophic Factor- a protein that is vital for survival and development of brain cells. It even boosts antioxidant defences by regulating mitochondrial function in the neurons (mitochondria are respiratory and energy-producing units of the cells).

One of the prime reasons for using acetylcarnitine to treat neuropathy is its ability to support nerve regeneration. It not only increases the number of nerve fibres during regeneration but also improves the quality of regeneration.

Myelin is the insulating cover that supports and protect neurons. Acetylcarnitine is also found to be involved in formation and maintenance of myelin sheath.

These properties suggest that acetylcarnitine is vital for maintaining nerve health and function. Studies in patients with mono or polyneuropathies caused by different factors have reported that ALC improves nerve function and physiological parameters associated with nerve health.


Quick Gist: Acetyl-L carnitine protects the brain and nervous system. It also supports regeneration of nerves. These therapeutic properties contribute to its benefits in neuropathy.

Studies conducted in humans have also confirmed that acetyl-L-carnitine not only reduces neuropathy related symptoms but even improves nerve function.

4.Acetyl-l-carnitine relieves neuropathic pain
 
In 1995, Onofrj et al. demonstrated that acetylcarnitine injections (1g per day) for 15 days helped relieve neuropathic pain in patients.

As I mentioned earlier, ALC activates metabotropic glutamate receptor to relieve neuropathic pain. Glutamate is a neurotransmitter and glutamate receptors are involved in pain transmission.

A study published in Journal of Neuroscience, 2009 reported that acetylcarnitine ameliorates neuropathic pain by preventing activation of apoptotic pathway and reducing mitochondrial dysfunction.

Acetyl-L-carnitine works as an epigenetic agent- it can regulate the process by which our genes are switched on and off. This epigenetic action helps increases the activity of metabotropic glutamate receptors to relieve neuropathic and inflammatory pain.

A recent study published in Molecular Pain, 2017 compared the effects of conventional medicines prescribed for neuropathic pain with ACL in an animal model of nerve injury.

The pain relief effect (in case of inflammatory pain) of pregabalin, amitryptiline, and ceftriaxone lasted only seven days after stopping treatment while the analgesic effect of acetyl-L-carnitine lasted for 14 days after drug withdrawal.

Similarly, in case of neuropathic pain, the analgesic effect of conventional medicines lasted only for 15 days after the end of the treatment while that of acetylcarnitine lasted for 37 days after treatment cessation.

A recent review study published in PloS One, 2015 confirmed that acetyl-L-carnitine has a moderate effect in reducing neuropathic pain and is a safe therapeutic agent.


Quick Gist: Acetyl-L-carnitine has an analgesic effect and relieves neuropathic pain in patients with peripheral neuropathy. It’s pain relieving effect lasts for a longer duration than conventional medicines prescribed for nerve pain.

Dosage of Acetyl-L-Carnitine For Peripheral Neuropathy

As per the research studies, the beneficial dose of acetyl-L-carnitine is 1000-2000mg daily. Start with a small dose (500mg daily) and scale up gradually; a dose of 1000mg -1500mg per day should help.

Some patients may require acetylcarnitine injections or high dose therapy. Please consult a health practitioner before taking acetyl-L-carnitine supplements.

Precautions with Acetyl-L-Carnitine Use

Acetyl-L-carnitine is safe and well tolerated at recommended doses (500-1000mg per day). High doses can have side effects such as nausea, retching and gastric discomfort.

Other adverse events noted in studies with ALC use in neuropathy are a headache, hyperesthesia (increased sensitivity to touch), pins and needles sensation, biliary colic (pain similar to that of a gallstone attack).

The has been one case report that noted worsening of psychosis in a patient with bipolar disorder.

ALC is proven to be beneficial for treating various heart-related disorders, but if you are already taking medications for the same, please consult your doctor before taking acetylcarnitine.

Carnitine and its derivatives may regulate thyroid hormone levels; if you have thyroid disorders, please take ALC with caution.

About the use of acetyl-L-carnitine for chemotherapy-induced neuropathy, there is a bit of conflict when it comes to recommending this therapy. Some studies have found it beneficial in case of paclitaxel and cisplatin chemotherapy-induced neuropathy.

But some clinical trials have found it ineffective, and one has even reported worsening of symptoms.

Researchers from Maxima Medical Centre, The Netherlands have reported that use of chemotherapeutic agents may cause urinary excretion of carnitine and related compounds and contribute to carnitine deficiency. This warrants the need for better research on the use of acetylcarnitine in chemotherapy-induced neuropathy.

Please consult a health practitioner before using acetyl-L-carnitine supplements especially in case of chemotherapy-associated neuropathy.

Conclusion

Acetyl-L-carnitine protects nerve health by regulating neurotransmitter levels, supporting nerve regeneration, protecting from neurotoxicity, reducing oxidative stress and inflammation.

The properties of acetylcarnitine make it beneficial for treating peripheral neuropathy. ALC benefits in diabetic neuropathy by regulating nerve as well as metabolic health.

Studies in humans show that it effectively reduces nerve pain and it’s analgesic effect lasts for a longer duration than that of conventional medicines.

Acetyl-L-carnitine is also known as a cognition enhancer, and it may work well with alpha lipoic acid (ALA is good for neuropathy). Please consult a health practitioner before taking acetyl-L-carnitine supplements.

https://www.salubrainous.com/acetyl-l-carnitine-for-neuropathy/