How Hyperhidrosis Is Diagnosed

Diagnosing hyperhidrosis may be a very complex, or it may be a simple process, depending on the underlying cause. For example, if a person is diagnosed with primary focal hyperhidrosis, the diagnostic criteria are relatively straight forward and simple. On the other hand, for those with secondary general hyperhidrosis, the underlying cause could be one of many different origins; in this instance, a variety of lab tests and diagnostic procedures may be needed. But either way, the initial appointment will involve a physical exam, medical history, and some basic tests to determine if a person has hyperhidrosis.

Self-Checks/At-Home Testing

There are questionnaires designed to help a person who is experiencing excessive sweating to determine whether the sweating is problematic, or simply normal sweating. Here are some sample questions for a self-check at home from the International Hyperhidrosis Society:

1. How often (in a day) do you think about sweating or worry about sweating?
2. Do you change your clothes or bathe frequently? If so, how many times during the day?
3. Do you carry materials such as towels, antiperspirants, extra clothes, pads, or other items with you to help deal with your sweat?
4. Do you feel that you need to buy new shoes or clothing more frequently than others, due to sweating?
5. How many different types of products (such as antiperspirants, powders or deodorants) have you tried to manage sweating?
6. Have you ever avoided social contact, or changed plans for a social engagement due to fear of sweating?
7. Does excessive sweating often result in damage to paperwork, reading material, electronic devices or other items?
8. Does sweating interfere with your school, a job or your career goals?
9. Do you often have infections or irritated skin as a result of excessive perspiration or from using products to manage sweating?
10. Are you often concerned or upset about sweating in public?
11. Do you often sweat when having contact with others, or when anticipating upcoming interactions with others?
12. Have you ever lost a friend or a potential romantic partner due to excessive sweating?

The answers to the questionnaire will provide a clue as to just how symptoms are impacting your daily life and activities. Your answers will be helpful for the healthcare provider in assessing how sweating affects your overall quality of life, daily activities, as well as your psychological and social well being. These questions may be part of the diagnostic assessment that will help your healthcare provider more accurately diagnose your condition. You can print out a copy of an online worksheet, keep track of your answers, and take the worksheet with you when you visit the healthcare provider for an initial evaluation.

Physical Examination

During the initial consultation, a healthcare provider will perform a physical exam and gather information on your health history. The exam will include taking a very close look at the areas of the body where excessive sweating occurs. If possible, a dermatologist or other healthcare provider may want to observe how severely sweating occurs. The diagnosing physician may look for stains on clothing to assess axillary (under the armpit) sweating. A sweat stain of less than 5 centimeters (approximately 2 inches) is considered normal. The bigger the sweat stains that can be measured, the more severe the hyperhidrosis condition is, ranging from mild to moderate or severe.

For diagnosing palmar (on the hand) hyperhidrosis, your healthcare provider may evaluate the severity of moisture on your hands during the physical exam. Moisture without visible drops would indicate mild palmar sweating. Sweat that drips off the ends of the fingers indicates severe palmar sweating.

If visible sweating cannot be seen during the doctor’s visit, information may need to be gathered by the physician by asking interview questions instead of directly assessed first-hand. Sweating in discreet areas, such as under the breasts, buttocks, or other areas may be best evaluated by using the patient’s description.

Labs and Tests

Diagnostic tests for hyperhidrosis focus on sweat tests. However, you can expect blood and urine tests to be performed to check your general health and screen for other health problems that might be secondary causes of hyperhidrosis.

Sweat Tests

Minor’s starch iodine test: This test is helpful in diagnosing hyperhidrosis, particularly for detecting focal hyperhidrosis. This test involves using an iodine solution which is applied to the skin and then starch powder is applied on top of the iodine. When the two substances are placed in an area of the skin, a violet color will appear. This allows that diagnosing physician to easily view and measure the area/s that sweating occurs. The absence of color may indicate that focal hyperhidrosis is not the correct diagnosis.

The Quantitative Sudomotor Axion Reflex Test (QSART): This diagnostic test is used to measure the nerves that control sweating. This test is conducted using mild electrical stimulation on the skin (called iontophoresis).

Gravimetry: Other tests that may be employed to measure the amount of sweat a person is experiencing including the use of gravimetry. Gravimetry involves using filter paper (that is weighed before the test) which is inserted under the armpit (or on other areas of the body, such as the palms of the hands) for a specific amount of time. Next, it is removed and then weighed again after each time interval from 60 seconds up to five minutes.  The amount of sweat released at each time interval is measured and expressed as milligrams (mg)/time. A value of over 50 mg/min in the axillary (armpit) area, or more than 20 mg/min on the palms, indicates a diagnosis of hyperhidrosis.

According to a study published in the journal Clinical Autonomic Research, gravimetry is “easy, reproducible and fast method of evaluation of sweating. The reference values are stable and can serve as a qualifying and follow-up tool for evaluation of the patients with PHH [primary hyperhidrosis]."

Other Tests

When the diagnosis of hyperhidrosis is secondary generalized hyperhidrosis, the diagnosing physician may need to perform several other tests to discover the primary (underlying) cause of sweating. This may involve urine, blood or other lab tests to diagnose medical conditions that could be causing hyperhidrosis.

Hyperhidrosis Diagnoses

There are several hyperhidrosis diagnoses that the healthcare provider may identify, these include:

Primary focal hyperhidrosis: The most common form of hyperhidrosis, involves sweating in one or more “focal” areas of the body, the most common areas that primary focal hyperhidrosis occurs is on the palms of the hands, under the arms and the soles of the feet. But, focal hyperhidrosis may also involve sweating of the face, head, or forehead. Primary focal hyperhidrosis, also referred to as focal hyperhidrosis, often begins during childhood.

Unspecified: Excessive sweating associated with an inability to define the underlying cause

Secondary hyperhidrosis: The sweating occurs throughout the entire body (or is “generalized” instead of in a specific focal area). This type of sweating usually begins in adulthood and is likely to involve sweating while asleep. Secondary focal hyperhidrosis is caused by a secondary disorder.

Secondary focal hyperhidrosis: Secondary hyperhidrosis which is experienced in one or more focal areas (instead of being generalized throughout the body)

Other eccrine sweat disorders: Eccrine describes the body’s primary sweat glands; a diagnosis of other eccrine sweat disorders describes a sweating condition other than hyperhidrosis.

Depending on the area that sweating occurs, there are several names/diagnoses that further describe hyperhidrosis, these include:

• Axilla (under the armpit)
• Face
• Palms (on the hands)
• Soles (on the feet)

Criteria for Primary Focal Hyperhidrosis

The diagnostic criteria (signs and symptoms that must be present to diagnosis a specific disease) for primary focal hyperhidrosis includes excessive sweating which occurs for six months or more in duration, along with four or more of the following:

• Sweating occurs in the axillary (under the armpits) soles of the feet, palms of the hands, face, and head.
• Sweating occurs on both sides of the body
• Sweating is absent at night
• Sweating occurs at least once a week
• Sweating begins at 25 years of age or younger
• There is a family history of hyperhidrosis
• Symptoms cause impairment in daily activities

These criteria clearly differentiate the difference between primary focal hyperhidrosis and secondary hyperhidrosis and are intended to help the physician provide the optimal treatment.

Differential Diagnosis

The process of differentiating between two (or more) medical conditions that have the same or similar symptoms is called a differential diagnosis. There are several conditions that have the same signs and symptoms of hyperhidrosis. The body’s regulation of heat depends on its ability to sweat and cool the body off. In many situations, the sweat glands are overactive, such as when the external temperature climbs, during extreme stress, nervousness, exercise, and more. Sweating that occurs only during these situations is considered normal and would not be considered differential diagnoses, rather, associated medical conditions must exist, the most common include:

Endocrine Conditions

• Hyperthyroidism
• Hypopituitarism
• Diabetes
• Menopause
• Hypoglycemia
• Pregnancy

Neurologic Conditions

• Parkinson's disease
• Spinal cord injury
• Stroke
• Vasovagal syndrome (a fainting disorder that occurs in response to certain triggers)
• Hypothalamic hyperhidrosis (involves the perception in the brain that the body is too hot)
• Reflex sympathetic dystrophy (a disorder causing long term pain that commonly occurs after an injury such as a stroke)

Neoplastic Conditions (Conditions Involving Tumors)

• Tumors of the central nervous system (CNS)
• Hodgkin disease
• Myeloproliferative diseases (malignant diseases of bone marrow cells)
• Cancer of the thoracic cavity (chest)

Infectious Disorders

• Feverish conditions
• Tuberculosis
• Septicemia

Other medical conditions and underlying causes of hyperhidrosis include certain drugs, toxicity (from alcoholism or drug use) and more. Each of the above conditions causes secondary, generalized, diffuse sweating, except spinal cord injury and reflex sympathetic dystrophy, which involve sweating in focal areas.