ANNOUNCER: The nervous system of the body is divided into two major parts. The central nervous system consists of the brain and spinal cord, and the peripheral nervous system includes, but is not limited to, the nerves of the arms, hands, legs, feet, and toes. Peripheral neuropathy is the term for damage to the nerves of the peripheral nervous system. It can be caused by a variety of conditions such as vitamin deficiencies or shingles. However, in the United States, it is most commonly found in people with diabetes.
ASTRID ALMODOVAR, MD: Diabetic peripheral neuropathy is caused by chronic high glucose levels in the blood that damage nerve cells. The manifestations can be painful, or an absence of pain. For example, the patient can have burning, tingling sensation, or they could have no pain. They could have anesthesia in certain parts of their body, usually in the legs and the hands.
ANNOUNCER: Diagnosis and treatment of diabetic peripheral neuropathy involves a two-fold approach.
ROY FREEMAN, MD: In any individual who has diabetic peripheral neuropathy, it's absolutely vital to make every attempt to slow the progression and delay the appearance of the features of the peripheral neuropathy. In addition and simultaneously with this, it's vital to treat the symptoms of the peripheral neuropathy.
ANNOUNCER: The first step in delaying the progression of peripheral neuropathy is to control the patient's diabetes. The patient and the healthcare provider can work together to decide the best way to control blood sugar levels.
ROY FREEMAN, MD: Since the nerve damage is a direct consequence of the elevated blood glucose, it's vital that blood glucose be tightly monitored. Patients should control their diet carefully, exercise and also, under medical supervision, appropriately use prescribed medications, both oral medications and insulin, if necessary.
RUSSELL K. PORTENOY, MD: Patients with painful diabetic polyneuropathy have to have frequent measurements of their blood glucose, and also measurement of their hemoglobin A1C. Hemoglobin A1C is an indicator in the blood of how well the person's glycemic control, meaning to say how well their diabetes has been controlled, during the past period of time measured in weeks.
Most people would say that the hemoglobin A1C should be below 7 percent, and that if it goes above 7 or 7.5 percent, then the person needs much more aggressive management.
ANNOUNCER: In addition to controlling the patient's diabetes, there are many options for controlling the most debilitating symptom of DPN: pain.
ASTRID ALMODOVAR, MD: The pain of diabetic neuropathy can impact a patient's life in a very, very negative way. It is a pain sometimes that does not go away. It is something that inhibits or interferes with their ability to sleep, and therefore it's going to go on to cause fatigue, irritability during the day.
ROY FREEMAN, MD: For the treatment of neuropathic pain, it is unfortunate that the standard analgesics, the over-the-counter, non-steroidal anti-inflammatory drugs are not effective. Ibuprofen, naproxen do not work effectively to treat neuropathic pain. Fortunately, over the past ten, fifteen years, we've realized that a number of non-traditional analgesic agents work to treat neuropathic pain quite effectively.
Perhaps the group of agents which have the longest track record in the treatment of neuropathic pain are the tricyclic anti-depressants, drugs like amitriptyline, desipramine, nortriptyline and these are quite effective in the treatment of neuropathic pain. Unfortunately, they have an array of side effects that renders them intolerable to many patients. Older patients will often become drowsy and confused on these drugs. They may cause urinary retention and constipation. And while they are effective, the constellation of side effects that's associated with their use often minimizes our ability to use these drugs.
In addition to the anti-depressants, the anti-convulsants have been used to treat neuropathic pain. These are moderately effective.
ANNOUNCER: Opioids such as oxycodone and morphine are another category of medications that may be prescribed to relieve painful DPN. However, they are not first line treatment options and must be used with extreme caution.
ROY FREEMAN, MD: The opioids do have a role to play in the treatment of neuropathic pain. Obviously, there is concern when using any drug that has potential for abuse, potential for addiction, but these are agents that may be used as supplementary agents in combination with either an anti-depressant, or an anti-convulsant, or both to treat neuropathic pain.
ANNOUNCER: Recently, there have been two new drugs approved by the FDA to treat neuropathic pain.
ROY FREEMAN, MD: These are the first two drugs that have been approved by the FDA for the treatment of neuropathic pain, the anti-depressant duloxetine and the anti-convulsant pregabalin.
ANNOUNCER: Duloxetine is an anti-depressant which is somewhat different than the tricyclics. It has a better side effect profile and the onset of action is faster. Pregabalin is an anti-convulsant and also has a faster onset of clinical effects when compared to older agents.
In addition to oral medications, there are two topical agents that have been used in the treatment of neuropathic pain with varying results: lidocaine cream and capsaicin cream.
There are also a few mechanical devices that may be helpful to some patients.
ASTRID ALMODOVAR, MD: In terms of the feet, we would have orthotics, something that we could put inside the shoe to protect the affected area that might be more prone to ulceration. And, also, for example, if you have carpal tunnel-type of symptoms, then we use support for the wrists to alleviate the pain.
ANNOUNCER: Outside of medical treatments, there are several precautions that patients with DPN can take to reduce pain and help prevent the development of more serious complications.
RUSSELL K. PORTENOY, MD: All patients with diabetic polyneuropathy really need meticulous foot care. And this is because injury can occur to the skin, and as a result of the sensory loss, the patient may not perceive the injury, and it can rapidly progress and produce a serious complication, like a deep or non-healing ulcer or an infection of the underlying bone.
ASTRID ALMODOVAR, MD: So they need to inspect their feet every day, between their toes, underneath, use a mirror. Another thing they have to do is to make sure that they lubricate their feet very well and they use socks, preferably with their seams outside. Therefore, they don't cut themselves with it.
Another precaution would be to make sure their shoes have nothing inside. So before you put your shoes on, make sure that you shake them and you make sure there's nothing in them that might affect your circulation or cut you.
ANNOUNCER: Additionally, patients who have sensory loss from DPN are discouraged from cutting their own toenails. Doing so could result in unnoticed injuries, which are susceptible to infection.
Fortunately, there have been many advances in pain management. Patients with DPN have more treatment options than ever before, although finding the right combination may take time.
ROY FREEMAN, MD: I think patients must be patient when they take medications. So work with a physician or a medical caretaker who is willing to slowly go through the various medications that are available, and it's likely that either soon, or sooner rather than later, an effective means will be found to substantially ameliorate neuropathic pain.
ANNOUNCER: And by understanding their disease, people with diabetes can significantly reduce the impact of peripheral neuropathy on their lives.
ASTRID ALMODOVAR, MD: The most important thing is that they know what the complications are, they know how to do their self-care, and that they understand that improving their diabetes control will greatly improve their symptoms and their quality of life.