Peripheral Neuropathy: Damage to nerves outside of the central nervous system; neuropathy commonly affects the feet, although the hands can be involved as well. Symptoms include tingling and pain in the extremities, as well as numbness. Usually, both sides are affected. Neuropathy can be caused by HIV itself, or by drugs such as ddC (Hivid), d4T (Zerit), ddI (Videx) and 3TC (Epivir)

Peripheral neuropathy (PN) is a relatively common side effect from some anti-HIV drugs. It can also be caused by HIV itself. It is difficult to know the cause but if the numbness or pain is symmetrical in both hands or both feet it is more likely to be a side effect of treatment. The 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 neuropathy gets worse it can become very painful. It is a side effect that you should take very seriously. PN is mainly associated with nucleosides, especially the 'd' drugs. PN has been reported in studies of ddC (now rarely used), ddI, d4T and less frequently with 3TC.

Using more than one of these drugs together can increase the risk as can use of other drugs such as hydroxyurea, dapsone, thalidomide, isoniazid and vincristine.

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

Recent neuropathy studies have measured nerve damage in skin in a small biopsy sample.

Simple tests include comparing ankle and knee reflexes or to test sensations from the toes up the leg with an ordinary pin. A tuning fork will show a reduced vibration in a foot with neuropathy.

It is common for doctors to underestimate how much pain people are experiencing because they think that their patients always exaggerate pain. In fact, most people underestimate pain.

The earlier you switch treatment, and the less severe the side effects, the more likely that the symptoms will reverse, but this does not happen for everyone.

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 may be the best thing you can do – neuropathy can be irreversible and debilitating.

If d4T is the cause of your neuropathy it may be possible to reduce the twice-daily 40mg dose to 30mg (or even 20mg) twice daily. For this approach it may be better to stop all drugs for a couple of weeks before restarting with the lower dose.

Your choices depend on your previous drug history and you should talk through all the possibilities with your doctor – you still have to consider your HIV treatment but avoidance of neuropathy altogether is the best way of treating it.

If you do stop using the drug you think is responsible (by switching to another or stopping all treatment altogether) then you may have to wait up to two months to know how much the discontinuation has helped. Often during this time symptoms can continue to get worse before you notice an improvement.

There are currently no treatments that are approved to repair or regrow damaged nerves. One study has shown that L-acetyl carnitine (Alcar) can lead to nerve improvement.

Research into a synthetic human Nerve Growth Factor (hNGF) in the US, which looked promising, has since been put on hold and development halted.

Treatments that are prescribed to manage neuropathy are basically used to mask the pain. Sometimes these painkillers can have side effects themselves that make them difficult to use.

Amitriptyline, nortriptyline and gabapentin don’t reduce the pain, but change how your brain perceives it. Gabapentin (up to 1200mg, three times a day) has been reported as being effective. These drugs work for some people but others find their sedative properties too difficult – even when they ease the pain from neuropathy.

Opiate-based painkillers such as methadone, morphine and codeine, although not always appropriate for neurological damage, sometimes benefit people with severe symptoms. It sometimes takes several days to find the appropriate dose, and these drugs can interact with some HIV drugs. A side effect of opiates is constipation.

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.

L-acetyl carnitine (Alcar) is a supplement that has been effective in small studies and anecdotally. It is being studied again in the UK, US, France and Italy for PN.

Acupuncture has also become a lifeline for many people who report improved quality of life. A study comparing acupuncture to placebo showed no benefit, but the acupuncture was a standardised rather than individualised treatment. It is definitely worth trying in order to decide for you.

Magnets – Using magnetic insoles have reported benefits in diabetic-related neuropathy.

Local anaesthetic creams such as Lidocaine (5%).

Capsaicin – Topical cream made from chilli peppers that causes increased local blood flow when applied to the skin. Mixed reports, many of them not encouraging.

Voltarol (NSAID) – a nonsteroidal anti-inflammatory.

Alpha-Lipoic Acid – 600 to 900mg daily may 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.

The neuropathy association: www.neuropathy.org

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