Causes of Lack of Sweating

Causes of Anhidrosis

Anhidrosis, characterized by a lack of sweating in one or more areas of the body, occurs even when temperatures rise. Sweating plays a crucial role in regulating body temperature, and the inability to sweat can lead to dangerously elevated body heat. Anhidrosis may manifest as a symptom of various health issues or as a standalone condition. Identifying the primary cause can be challenging due to the range of potential underlying factors. In some cases, sweat glands may cease to function altogether, or they may not operate effectively. Natural perspiration levels tend to decrease with age, and certain health conditions, especially those affecting glandular function, such as certain autonomic nervous system disorders like diabetes, may further restrict sweating in older adults.

Skin Disorders and Injuries

Anhidrosis can result from various skin disorders that block sweat glands, preventing sweating. Notable disorders include:

• Psoriasis: This condition involves rapid skin cell production in specific areas, exceeding the typical rate by tenfold, resulting in raised, red, scaly patches on the skin.
• Leprosy: Also known as Hansen’s Disease, it significantly impacts the eyes, oral mucosa, nasal membrane, upper respiratory tract, peripheral nerves, and skin.
• Ichthyosis: A genetic skin disorder characterized by dry, thickened skin due to the accumulation of dead skin cells.
• Exfoliative Dermatitis: This skin disorder may arise from prior cancer types, certain medications, or other skin diseases, sometimes without a clear cause, leading to widespread peeling and rashes.
• Heat Rash: A skin rash caused by blocked sweat glands, resulting in red bumps and blisters that can sometimes be itchy or tingly.
• Skin Irradiation Injuries: Damage to the skin from radiation exposure.
• Pore Occlusion Disorders: These are among the most common causes of anhidrosis.
• Severe Skin Injuries: Third-degree burns from fire, electricity, chemicals, or overdose of certain medications can impede sweating.
• Bacterial Infections or Dead Cells: These can block sweat glands.

Dehydration

Dehydration refers to a decrease in the body’s natural fluid levels without timely replenishment. This condition can impair normal bodily functions and elevate the risk of heatstroke, a serious concern that disrupts the body’s mechanisms for handling increased temperatures, including sweating. Heatstroke often results from strenuous exercise or exposure to hot weather, leading to difficulty in balancing lost and ingested fluids. Dehydration can range from mild to severe based on the amount of fluid lost, with risks increasing in older individuals or those with specific health issues like diabetes.

Nerve Injuries

Injuries to the nerves that regulate the autonomic nervous system can affect the functionality of sweat glands, as this system is responsible for controlling involuntary processes including blood pressure and organ functions. Several disorders that impact the nervous system can lead to impaired sweat gland functioning, including:

• Parkinson’s Disease.
• Multiple System Atrophy (MSA).
• Horner’s Syndrome, which affects the eyes and face.
• Amyloidosis, involving abnormal protein accumulation impacting the nervous system.
• Ross Syndrome, characterized by abnormal pupil dilation and sweat gland dysfunction, a rare genetic disorder.
• Nerve damage from leprosy.
• Peripheral neuropathy associated with paraneoplastic syndrome.
• Pure Autonomic Failure (PAF).
• Harlequin Syndrome.
• Alcoholic Peripheral Neuropathy caused by excessive alcohol consumption.
• Guillain-Barre Syndrome.
• Diabetic Autonomic Neuropathy, affecting sweating due to poor blood glucose regulation.

Congenital and Hereditary Disorders

There are several congenital and hereditary disorders that can impact sweat gland functionality, including:

• Congenital Dysplasias: Genetic disorders present at birth affecting the growth or absence of sweat glands.
• Fabry’s Disease: A genetic condition impacting metabolic processes and sweating.
• Hypohidrotic Ectodermal Dysplasia: A genetic condition leading to a significant or complete absence of sweat glands.
• Congenital Disorders: Such as congenital insensitivity to pain or lack of sweating.

Connective Tissue and Autoimmune Disorders

Some connective tissue and autoimmune disorders may also lead to anhidrosis, including:

• Sjögren’s Syndrome: This condition affects sweat glands and causes dryness in the mouth and eyes.
• Progressive Systemic Sclerosis (Scleroderma): A disorder that affects the skin and connective tissue, leading to hardening and potential peripheral nerve damage, it is a rare degenerative autoimmune disease.
• Lupus: An autoimmune disease that also impacts the peripheral nervous system and skin.
• Graft-versus-Host Disease (GVHD): Involving immune cells from a bone marrow donor attacking the recipient’s sweat glands.

Medication-Induced Anhidrosis

Certain medications can induce anhidrosis, including:

• Anticholinergic Drugs: These medications may be used to mitigate side effects from antipsychotics. Examples include Procyclidine, Biperiden, Orphenadrine, Benzhexol, and Benztropine.
• Tricyclic Antidepressants (TCAs): Commonly used to treat depression but can have anticholinergic effects, often leading to their replacement with alternatives.
• Carbonic Anhydrase Inhibitors: Such as Dorzolamide, Methazolamide, Topiramate, and Acetazolamide are used in various treatments, including for glaucoma and osteoporosis. They may also be used as diuretics or for altitude sickness.
• Other Medications: Like Morphine and Botulinum toxin type A.

Other Contributing Factors

Additional factors that may lead to anhidrosis include:

• Injury to sweat glands.
• Lung cancer, which may cause anhidrosis on one side of the body while leading to hyperhidrosis on the other.
• Breast silicone implants, in some rare cases, have been linked to reduced sweating.

Idiopathic Anhidrosis

In some instances, anhidrosis may be classified as idiopathic, as seen in Acquired Idiopathic Generalized Anhidrosis (AIGA). Here, individuals may experience discomfort and pain as their body temperature rises to trigger sweating, even with minimal increases in temperature. Symptoms typically subside once the body cools down. This condition is more prevalent in young males, who often seek medical advice due to exercise-related difficulties stemming from painful symptoms. Oral corticosteroids have proven effective in treatment, although relapses can occur. Symptoms may include:

• Itching.
• Sharp pain.
• Skin rashes.
• Chills created by exertion or other triggering factors, such as cholinergic urticaria, which affects nearly half of those with this disorder.
• Increased risk of heatstroke.

Risk Factors

Certain risk factors may elevate the likelihood of developing anhidrosis, including:

• Advancing age.
• Diabetes, which can disrupt sweat gland function.
• Skin scarring preventing the healing of damaged sweat glands.
• Genetic mutations impacting sweat gland functionality.

Prevention of Anhidrosis

Anhidrosis often cannot be prevented; however, certain recommendations can help mitigate risks associated with conditions linked to elevated body temperatures, such as:

• Avoiding outdoor activities during peak heat.
• Wearing lightweight, loose-fitting clothing in hot weather.
• Using misting sprays to cool the body.
• Staying informed about disorders related to elevated body temperatures and their management.
• Monitoring physical activities to prevent exhaustion.