Peripheral neuropathy

Hand pain

Peripheral = furthest away, neuro = nerve, pathy = damage.

Peripheral neuropathy (PN) is NOT a side effect of modern HIV drugs. It can be caused by non-HIV drugs like ribavirin and cancer drugs.

PN was mainly caused by very early HIV drugs that are no longer used or made. These are d4T (Zerit, stavudine), ddI (Videx, didanosine) and ddC (Hivid, zalcitabine).

PN can be caused by HIV though, especially at low CD4 counts (under 100 cells/mm³). It is also a complication of diabetes, and rates of diabetes are increasing as people living with HIV get older.

Symptoms include increased sensitivity or numbness, or tingling in your hands and/or feet. Often it is something you hardly notice, or that comes and goes.

If this is a side effect rather than a result of HIV or diabetes, symptoms tend to be symmetrical in both hands or both feet.

If neuropathy gets worse it can become very painful. Please take early symptoms seriously.

Non-HIV drugs that cause PN include dapsone, thalidomide, isoniazid, vincristine and some cancer treatments.

Alcohol, smoking, amphetamines, deficiency of vitamins B12 and E and other illnesses like diabetes and syphilis can also cause and make neuropathy worse. B12 and folate levels can be tested.

Can PN be measured?

Simple tests for PN include comparing ankle to knee reflexes, or using a pin to test sensations from the toes up the leg.

A tuning fork will show a reduced vibration in a foot with neuropathy. Some studies directly measured nerve damage in skin in a biopsy sample.

Your doctor might just rely on what you report is happening. If your symptoms are causing you discomfort or pain, you must make sure it is taken seriously.

Sometimes doctors think their patients overestimate how much pain they are in. In fact, most people underestimate pain when talking to their doctor.

Sensitivity tests that measure your reactions to different pressure are not used so frequently, and it can sometimes take 4-6 weeks to get the results. Getting these results recorded regularly though can help you measure any worsening of the symptoms.

Is neuropathy reversible by switching treatment?

The earlier you switch treatment when symptoms are still mild, the more likely that they will reverse.

Moderate and severe neuropathy very rarely resolves fully but switching drugs can stop the symptoms getting worse. If you have other drugs to use, switching at the first sign of symptoms might be the best thing you can do. Neuropathy can be irreversible and debilitating.

d4T is rarely used in Western countries because of this and other side effects. If d4T is the cause of your neuropathy and you cannot change treatment you can reduce dose. The original twice-daily 40mg dose can be reduced to 30mg or even 20mg twice daily.

After switching, you might have to wait up to two months to know how much this has helped. Often symptoms can continue to get worse before you notice an improvement.

Treatments for neuropathy

For many years, there were no approved treatments to repair or regrow damaged nerves.

One very old study reported that acetyl-L-carnitine (Alcar) at a dose of 1500mg, twice daily, can lead to nerve improvement. Acetyl-L-carnitine can be prescribed on a named-patient basis. Very few clinics in the UK use this treatment.

Research into a synthetic human Nerve Growth Factor (hNGF) in the US which looked promising was then stopped.

However, more recent approaches including ectrical tretment to reroute nerve pathways and deep laser treatment how reported benefits in non-HIV related neuropathy. See below for links,

Pain management to mask the pain

Treatments prescribed to manage neuropathy are basically used to mask the pain.

Sometimes these painkillers can have side effects themselves which make them difficult to use.

Amitriptyline, nortriptyline (tricyclic antidepressants) and gabapentin and pregabalin (antiepileptic drugs) are used to treat neuropathic pain. They do not reduce the pain, but change how your brain perceives it. Even when they help they can be difficult to tolerate because of they also cause drowsiness.

Opiate-based painkillers such as codeine, dihydrocodeine, fentanyl, methadone, morphine and tramadol sometimes help when the pain is severe.

Although not always appropriate for neurological damage, they sometimes help. It can take several days to find the appropriate dose, and these drugs can interact with some HIV drugs. A side effect of opiates is constipation.

It is important that your doctor checks for drug-drug interactions before your start these drugs. Liverpool University’s HIV drug interactions website gives free of charge, up-to-date evidence based information.

www.hiv-druginteractions.org

Cannabis (marijuana), or synthetic versions such as nabilone (Cesamet) have been used to reduce pain related to neuropathy. They can be prescribed in the UK. Dronabinol (Marinol) is only approved in the US.

Capsaicin patches that contain chilli pepper are available in the UK. However, Capsaicin doesn’t repair the nerve damage and potentially makes it worse.

Anyone with chronic pain should also have appropriate care from a pain control nurse specialist, rather than your HIV doctor. They will be able to make a full assessment of your level of pain, and adequately prescribe medication to reduce it.

More rarely, when pain is so great that it is not treatable, alcohol can be injected into a nerve junction. Nerve blocks can be very effective when they work, and are a specialist procedure, but can also cause loss of sensation and sometimes produce unpredictable results.

Other treatment approaches are listed below, though there is limited research to support these.

Alternative treatments

Alternative treatments are often used to manage PN.

Although they are often supported by limited evidence, there are anecdotal reports on these approaches. With a condition that is painful, it is worth trying each of these in case they help (though not all at the same time).

MC-5A Calmare (scrambler) therapy. This is a medical device that uses electrical pulses to reroute nerve pathways to unlearn the pain signals to the brain. This has been reported in clinical studies, but not specifically for HIV. However, in two recent studies from 2019, one reported no benefit between actual or sham treatment while another reported a benefit.

Low level laser therapy has also been studied to reverse diabetic neuropathy. This study reported a benefit. and so did this one.

Acetyl-L-carnitine (Alcar) is a supplement that has been effective in small studies and anecdotally. Other studies did not find a benefit.

Acupuncture is annecdotally reported to improve quality of life but not supported by research. A study comparing acupuncture to placebo showed no benefit, but the acupuncture was a standardised rather than individualised treatment. This is one you need to decide for yourself.

Magnets – Using magnetic insoles have reported benefits in diabetic-related neuropathy, although a published study found little difference compared to placebo (sham) insoles.

Local anaesthetic creams such as Lidocaine (5%), and Lidocaine patches reported benefits in recent studies.

Capsaicin – Patches made from chilli peppers that causes increased local blood flow when applied to the skin. Although approved in Europe the FDA in the US did not approve the Qutenza patch for HIV neuropathy. This was because the studies did not show a clear benefit.

diclofenac (Voltarol, an NSAID) – a nonsteroidal anti-inflammatory drug.

Alpha-Lipoic Acid – 600 to 900mg daily might help protect nerves from inflammation.

Cod liver oil – One or two tablespoons a day has anecdotally produced beneficial reports, especially if the symptoms have not become very severe. This is not as bad as it sounds as modern oils are palatable and also come in flavours.

Topical aspirin – suggested in one recent study that aspirin, crushed and dissolved in water or gel and applied to the painful area can relieve symptoms.

Vitamin B6 (pyridoxine) – requires caution with dosing as B6 can also worsen neuropathy (100mg daily is sometimes recommended).

Vitamin B12 – available as injections, lozenges, or nose-gel. B12 levels should be checked by your doctor. Dosage varies but if levels are too high this can worsen neuropathy.

Magnesium – 250mg – 2 capsules each morning.

Calcium – 300mg – 2 capsules each evening.

Other suggestions

Avoid tight fitting shoes and socks which restrict blood circulation.
Keep your feet uncovered at night – keeping them cooler and out of contact with sheets or bedding.
Try deep tissue massage.
Don’t walk or stand for long periods.
Soak your feet in cool water.

Management summary

Change HIV drug(s) that are responsible
Acetyl-L-carnitine (Alcar)
Cod liver oil
Painkillers such as gabapentin, amitriptyline or nortriptyline (or marujuana) might mask symptoms
Referral to a pain management clinic is important and can access a wider range of treatments