Central nervous system† disorders

Multiple system atrophy

Muscle stiffness

Slow, shaky movements

Loss of coordination and/or balance

Incontinence or inability to urinate

A doctor's examination

Sometimes MRI

Parkinson disease

Muscle stiffness

Tremor

Slow, shaky movements and a shuffling gait

Difficulty walking

Only a doctor's examination

Strokes if several have occurred

In people who are known to have had strokes

Only a doctor's examination

Spinal cord disorders

Syphilis that affects the spinal cord (tabes dorsalis)

Intense, stabbing pains in the legs that come and go

Unsteady walking

Decreased sensation in the legs and numbness or tingling

Blood tests and sometimes a spinal tap (to obtain cerebrospinal fluid) to check for syphilis

Tumors

Back pain

Muscle weakness and decreased sensation in the legs

MRI

Peripheral nerve† disorders

Amyloidosis

Numbness, tingling, and weakness

Biopsy

Nerve damage caused by diabetes, excessive alcohol use, or nutritional deficiencies

Often burning pain and/or numbness in the feet and hands

Sometimes weakness

Usually in people who are known to have a disorder that can cause nerve damage

Nerve conduction testing and electromyography

Pure autonomic failure

Sometimes decreased sweating and intolerance of heat

Constipation or loss of control over bowel movements (fecal incontinence)

Difficulty emptying the bladder

A doctor's examination

Blood tests

A decreased volume of blood (hypovolemia)

Dehydration

Thirst, decreased urination, and sometimes confusion

Only a doctor's examination

Excessive loss of blood

Often in people who have had an injury or surgery

Blood in stool or black, tarry stool

A doctor's examination, including testing stool for blood

A complete blood count

An underactive adrenal gland

Weakness and fatigue

Blood tests

Heart and blood vessel disorders

Abnormal heart rhythm

Sometimes chest pain

Palpitations (awareness of heart beats)

Fatigue

Shortness of breath

Symptoms often occur suddenly

Event monitor

Chronic venous insufficiency (causing blood to pool in the legs)

Long-lasting swelling in one or both legs

Chronic mild discomfort or aching in the ankles or legs but no pain

Sometimes reddish brown, leathery areas on the skin and shallow sores, usually on the lower legs

Often varicose veins

A doctor's examination

Heart failure

Shortness of breath and fatigue

A doctor's examination

Usually echocardiography (ultrasonography of the heart)

Heart attack (myocardial infarction)

Chest pain or pressure

Shortness of breath or fatigue

Sometimes in people who are known to have had a recent heart attack

ECG and blood tests to measure substances that indicate heart damage (cardiac markers)

Heart valve disorder

Shortness of breath

Often chest pain or pressure

Echocardiography

High levels of the hormone aldosterone (hyperaldosteronism) or catecholamines (pheochromocytoma), usually caused by a tumor in the adrenal gland)

Weakness, tingling, muscle spasms, high blood pressure, and headache

Blood tests

Drugs

In people known to use one of these drugs

A doctor's examination

Sometimes stopping the drug to see if symptoms go away

Drugs that affect the central nervous system: Antipsychotics (particularly phenothiazines), monoamine oxidase inhibitors, or tricyclic or tetracyclic antidepressants

In people known to use one of these drugs

Only a doctor's examination

Sedatives: Alcohol or barbiturates

In people known to use one of these drugs

Only a doctor's examination

In people known to use one of these drugs

Only a doctor's examination

Other problems

Age-related changes in blood pressure regulation

In older people

No other symptoms

Only a doctor's examination

Bed rest if prolonged

In people who have been at bed rest for a long time

Only a doctor's examination

A low level of potassium in the blood (hypokalemia)

Muscle weakness and cramping

Pins-and-needles sensation

Often in people who take certain diuretics

Blood tests