neuropathy

If you have diabetes, your blood glucose, or blood sugar, levels are too high. Over time, this can damage the covering on your nerves or the blood vessels that bring oxygen to your nerves. Damaged nerves may stop sending messages, or may send messages slowly or at the wrong times.

This damage is called diabetic neuropathy. Over half of people with diabetes get it. Symptoms may include:

• Numbness in your hands, legs, or feet
• Shooting pains, burning, or tingling
• Nausea, vomiting, constipation, or diarrhea
• Problems with sexual function
• Urinary problems
• Dizziness when you change positions quickly

Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. Controlling your blood sugar can help prevent nerve problems, or keep them from getting worse. Treatment may include pain relief and other medicines.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Nerves are like wires that carry messages back and forth between your brain and your body. Your peripheral nerves branch off from your brain and spinal cord and connect to all parts of your body, including your muscles and organs. Peripheral nerves carry messages from your brain that control your movement, breathing, heartbeat, digestion, and more. They also carry messages from your body to your brain, so you can feel things, such as pain, heat, and cold.

Peripheral nerve disorders happen when one or more peripheral nerves are damaged. Damaged nerves may not carry messages correctly, or they may not work at all. As a result, you may have pain, trouble walking, or a variety of other problems, depending on which nerves are involved.

Peripheral nerve disorders are very common. There are more than 100 different types.

Many things can damage nerves and lead to peripheral nerve disorders:

• Diabetes is the most common cause of peripheral nerve disorders. Most people with diabetes will develop diabetic nerve problems.
• Physical injury (trauma) that stretches, crushes, squeezes, cuts, or puts pressure on one or more nerves. Some examples of peripheral nerve disorders from physical injury include complex regional pain syndrome and brachial plexus injuries.
• Health conditions, including:
  • Certain cancers and their treatment (chemotherapy and radiation therapy).
  • Infections, such as HIV and Lyme disease.
  • Problems with blood or blood vessels.
  • Autoimmune diseases, such as rheumatoid arthritis and lupus.
  • Kidney or liver disease.
• Certain medicines.
• Contact with certain toxic substances, such as lead or mercury.
• Alcohol use disorder (AUD) and smoking.
• Vitamin imbalances, especially a lack of vitamin B12.
• Your genes, including changes in your genes or conditions that you inherit from your parents, such as Charcot-Marie-Tooth disease.

In certain cases, the cause of peripheral nerve disorder is not known.

The symptoms of peripheral nerve disorders depend on which nerves are affected, what is causing the damage, and how serious it is:

• Weak or aching muscles
• Problems with balance, walking, or using your arms and hands
• Cramps or twitching muscles
• Muscle shrinking

• Tingling, numbness, or pain often in the hands and feet
• Not being able to feel heat, cold, or pain, such as a cut on your foot
• Pain from even light touch

• A heartbeat that's too fast or too slow
• Trouble swallowing
• Sweating too much or too little
• Vomiting, diarrhea, or constipation
• Problems with urination or sexual function

Symptoms may range from mild to very strong. They may develop quickly over days or slowly over months and years. But they are rarely life-threatening.

To find out if you have a peripheral nerve disorder, your provider will:

• Ask about your medical history
• Ask about your family health history
• Do a physical exam
• Order tests, which may include:
  • Blood tests
  • Genetic tests
  • Nerve tests that measure:
    • Electrical activity in your nerves and muscles
    • How well your autonomic nerves are working
  • A biopsy of nerve or skin tissue
  • CT or MRI scan to see what may be pressing on your nerves

It's important to treat any conditions that are causing nerve damage. In certain cases, that will allow your nerves to heal over time.

Treatment for symptoms depends on the type of peripheral nerve disorder you have, where it is, and how severe. Treatment options include:

• Braces or splints
• Over-the-counter patches and skin creams
• Prescription medicines
• Non-drug pain management, such as electrical stimulation or relaxation therapy
• Surgery to relieve pressure on a nerve

You can help prevent peripheral nerve disorders by:

• Managing health conditions that may cause nerve damage, especially diabetes
• Preventing falls and accidents
• Avoiding toxic substances
• Being careful to avoid repeated motions and body positions that press on your nerves
• Eating a balanced diet, exercising, limiting alcohol, and not smoking

NIH: National Institute of Neurological Disorders and Stroke

Charcot-Marie-Tooth disease (CMT) is a group of genetic nerve disorders. It is named after the three doctors who first identified it. In the United States, CMT affects about 1 in 2,500 people.

CMT affects your peripheral nerves. Peripheral nerves carry movement and sensation signals between the brain and spinal cord and the rest of the body. Symptoms usually start around the teen years. Foot problems such as high arches or hammertoes can be early symptoms. As CMT progresses, your lower legs may weaken. Later, your hands may also become weak.

Doctors diagnose CMT by doing a neurologic exam, nerve tests, genetic tests, or a nerve biopsy. There is no cure. The disease can be so mild you don't realize you have it or severe enough to make you weak. Physical therapy, occupational therapy, braces and other devices and sometimes surgery can help.

NIH: National Institute of Neurological Disorders and Stroke

Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical condition such as alcoholism, a tumor, or a stroke. Other causes may include toxins, chemicals, and viruses. Sometimes the cause is unknown.

Degenerative nerve diseases include:

• Alzheimer's disease
• Amyotrophic lateral sclerosis
• Friedreich ataxia
• Huntington's disease
• Lewy body disease
• Parkinson's disease
• Spinal muscular atrophy

Degenerative nerve diseases can be serious or life-threatening. It depends on the type. Most of them have no cure. Treatments may help improve symptoms, relieve pain, and increase mobility.

Your autonomic nervous system is the part of your nervous system that controls involuntary actions, such as the beating of your heart and the widening or narrowing of your blood vessels. When something goes wrong in this system, it can cause serious problems, including:

• Blood pressure problems
• Heart problems
• Trouble with breathing and swallowing
• Erectile dysfunction in men

Autonomic nervous system disorders can occur alone or as the result of another disease, such as Parkinson's disease, alcoholism and diabetes. Problems can affect either part of the system, as in complex regional pain syndromes, or all of the system. Some types are temporary, but many worsen over time. When they affect your breathing or heart function, these disorders can be life-threatening.

Some autonomic nervous system disorders get better when an underlying disease is treated. Often, however, there is no cure. In that case, the goal of treatment is to improve symptoms.

NIH: National Institute of Neurological Disorders and Stroke

Diabetes is a disease in which your blood glucose, or blood sugar, levels are too high. Glucose comes from foods you eat. The cells of your body need glucose for energy. A hormone called insulin helps the glucose get into your cells.

With type 1 diabetes, your body doesn't make insulin. With type 2 diabetes, your body doesn't make or use insulin well. Without enough insulin, glucose can't get into your cells as quickly as usual. The glucose builds up in your blood and causes high blood sugar levels.

Foot problems are common in people with diabetes. They can happen over time when high blood sugar damages the nerves and blood vessels in the feet. The nerve damage, called diabetic neuropathy, can cause numbness, tingling, pain, or a loss of feeling in your feet.

If you can't feel pain, you may not know when you have a cut, blister, or ulcer (open sore) on your foot. A wound like that could get infected. The infection may not heal well because the damaged blood vessels can cause poor blood flow in your feet.

Having an infection and poor blood flow can lead to gangrene. That means the muscle, skin, and other tissues start to die. If you have gangrene or a foot ulcer that does not get better with treatment, you may need an amputation. This is a surgery to cut off your damaged toe, foot, or part of your leg. It may prevent a bad infection from spreading and could save your life.

But there's a lot you can do to prevent a foot wound from becoming a major health problem.

The best way to protect your feet is by controlling your blood sugar levels every day. This will help keep nerve and blood vessel damage from getting worse. The next step is to keep the skin of your feet healthy.

Good foot care for people with diabetes includes:

• Checking your feet every day. Look for cuts, redness, and other changes in the skin and toenails, including warts or other spots that your shoes could rub. Make sure to check the bottoms of your feet too.
• Washing your feet every day. Use warm water and soap. Don't soak your feet because that can dry out your skin. After you dry your feet, you can use talcum powder or cornstarch between your toes. They soak up moisture that can cause infection. If you use lotion, don't apply it between your toes.
• Asking your doctor how to remove corns and calluses safely. Thick skin on your feet can rub and lead to sores. But removing it the wrong way could damage your skin. So you don't want to cut the skin or use medicated pads or liquid removers.
• Trimming your toenails straight across with a clipper. If it's hard for you to trim your own toenails, or if they're thick or curve into the skin, have a podiatrist (foot doctor) do it for you.
• Always wearing well-fitting shoes and socks or slippers to protect your feet when walking. You don't want to walk barefoot, even indoors. And be sure your shoes are smooth inside. A seam or pebble could rub your skin raw.
• Protecting your feet from heat and cold. Use sunscreen on exposed skin and don't walk barefoot at the beach. In cold weather, wear warm socks instead of warming your feet near a heater or fireplace.
• Keeping the blood flowing in your feet. Put your feet up when you're sitting. Wiggle your toes and circle your feet throughout the day. Don't wear tight socks. And get plenty of activity that's not too hard on the feet, such as walking.
• Getting your feet checked at your health care visits. Even if you haven't noticed a problem, it's good to have your health care provider look at your feet.

Serious foot problems can develop quickly. See your health care provider right away if you notice:

• A cut, blister, or bruise on your feet that doesn't start to heal in a few days
• Red, warm, or painful skin on your feet
• A callus with dried blood inside
• A foot infection that becomes black and smells bad that could be gangrene

Remember, controlling your blood sugar and caring for your feet every day are the best steps you can take to prevent serious diabetic foot problems.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Metabolism is the process your body uses to make energy from the food you eat. Food is made up of proteins, carbohydrates, and fats. Chemicals in your digestive system (enzymes) break the food parts down into sugars and acids, your body's fuel. Your body can use this fuel right away, or it can store the energy in your body tissues. If you have a metabolic disorder, something goes wrong with this process.

Mitochondrial diseases are a group of metabolic disorders. Mitochondria are small structures that produce energy in almost all of your cells. They make it by combining oxygen with the fuel molecules (sugars and fats) that come from your food. When the mitochondria are defective, the cells do not have enough energy. The unused oxygen and fuel molecules build up in the cells and cause damage.

The symptoms of mitochondrial disease can vary. It depends on how many mitochondria are defective, and where they are in the body. Sometimes only one organ, tissue, or cell type is affected. But often the problem affects many of them. Muscle and nerve cells have especially high energy needs, so muscular and neurological problems are common. The diseases range from mild to severe. Some types can be fatal.

Genetic mutations cause these diseases. They usually happen before age 20, and some are more common in infants. There are no cures for these diseases, but treatments may help with symptoms and slow down the disease. They may include physical therapy, vitamins and supplements, special diets, and medicines.

The optic nerve is a bundle of more than 1 million nerve fibers that carry visual messages. You have one connecting the back of each eye (your retina) to your brain. Damage to an optic nerve can cause vision loss. The type of vision loss and how severe it is depends on where the damage occurs. It may affect one or both eyes.

There are many different types of optic nerve disorders, including:

• Glaucoma is a group of diseases that are the leading cause of blindness in the United States. Glaucoma usually happens when the fluid pressure inside the eyes slowly rises and damages the optic nerve.
• Optic neuritis is an inflammation of the optic nerve. Causes include infections and immune-related illnesses such as multiple sclerosis. Sometimes the cause is unknown.
• Optic nerve atrophy is damage to the optic nerve. Causes include poor blood flow to the eye, disease, trauma, or exposure to toxic substances.
• Optic nerve head drusen are pockets of protein and calcium salts that build up in the optic nerve over time

Contact your health care provider if you are having vision problems. Tests for optic nerve disorders may include eye exams, ophthalmoscopy (an examination of the back of your eye), and imaging tests. Treatment depends on which disorder that you have. With some optic nerve disorders, you may get your vision back. With others, there is no treatment, or treatment may only prevent further vision loss.

For most adults, moderate alcohol use is probably not harmful. However, about 18 million adult Americans have an alcohol use disorder (AUD). This means that their drinking causes distress and harm. AUD can range from mild to severe, depending on the symptoms. Severe AUD is sometimes called alcoholism or alcohol dependence.

AUD is a disease that causes:

• Craving - a strong need to drink
• Loss of control - not being able to stop drinking once you've started
• Negative emotional state - feeling anxious and irritable when you are not drinking

Binge drinking is drinking so much at once that your blood alcohol concentration (BAC) level is 0.08% or more. For a man, this usually happens after having 5 or more drinks within a few hours. For a woman, it is after about 4 or more drinks within a few hours. Not everyone who binge drinks has an AUD, but they are at higher risk for getting one.

Too much alcohol is dangerous. Heavy drinking can increase the risk of certain cancers. It may lead to liver diseases, such as fatty liver disease and cirrhosis. It can also cause damage to the brain and other organs. Drinking during pregnancy can harm your baby. Alcohol also increases the risk of death from car crashes, injuries, homicide, and suicide.

You may have an AUD if you can answer yes to two or more of these questions:

In the past year, have you:

• Ended up drinking more or for a longer time than you had planned to?
• Wanted to cut down or stop drinking, or tried to, but couldn't?
• Spent a lot of your time drinking or recovering from drinking?
• Felt a strong need to drink?
• Found that drinking - or being sick from drinking - often interfered with your family life, job, or school?
• Kept drinking even though it was causing trouble with your family or friends?
• Given up or cut back on activities that you enjoyed just so you could drink?
• Gotten into dangerous situations while drinking or after drinking? Some examples are driving drunk and having unsafe sex.
• Kept drinking even though it was making you feel depressed or anxious? Or when it was adding to another health problem?
• Had to drink more and more to feel the effects of the alcohol?
• Had withdrawal symptoms when the alcohol was wearing off? They include trouble sleeping, shakiness, irritability, anxiety, depression, restlessness, nausea, and sweating. In severe cases, you could have a fever, seizures, or hallucinations.

If you have any of these symptoms, your drinking may already be a cause for concern. The more symptoms you have, the more serious the problem is.

If you think you might have an AUD, see your health care provider for an evaluation. Your provider can help make a treatment plan, prescribe medicines, and if needed, give you treatment referrals.

NIH: National Institute on Alcohol Abuse and Alcoholism

Amblyopia, or "lazy eye," is the most common cause of visual impairment in children. It happens when an eye fails to work properly with the brain. The eye may look normal, but the brain favors the other eye. In some cases, it can affect both eyes. Causes include:

• Strabismus - a disorder in which the two eyes don't line up in the same direction
• Refractive error in an eye - when one eye cannot focus as well as the other, because of a problem with its shape. This includes nearsightedness, farsightedness, and astigmatism.
• Cataract - a clouding in the lens of the eye

It can be hard to diagnose amblyopia. It is often found during a routine vision exam.

Treatment for amblyopia forces the child to use the eye with weaker vision. There are two common ways to do this. One is to have the child wear a patch over the good eye for several hours each day, over a number of weeks to months. The other is with eye drops that temporarily blur vision. Each day, the child gets a drop of a drug called atropine in the stronger eye. It is also sometimes necessary to treat the underlying cause. This could include glasses or surgery.

NIH: National Eye Institute