Chronic Itching (Pruritus)
Chronic itching, also known as pruritus, is a persistent and often intense urge to scratch the skin that lasts for six weeks or longer. It can be a symptom of various underlying conditions, including skin disorders, systemic diseases, or nervous system issues.
Causes of Chronic Itching
1
Skin Conditions
Eczema, psoriasis, lichen planus, urticaria, contact dermatitis, and dry skin can all cause chronic itching.
2
Systemic Conditions
Kidney disease, liver disease, thyroid problems, diabetes, and blood disorders can also lead to chronic itching.
3
Neurological Causes
Nerve damage from conditions like shingles, multiple sclerosis, or stroke can cause itchiness in affected areas of the body.
4
Psychological Factors
Stress, anxiety, and psychogenic itch, an itch sensation with no clear physical cause, can contribute to chronic itching.
Medications and Pregnancy
Medications
Certain medications, including opioids, antibiotics, and statins, can cause pruritus as a side effect.
Pregnancy
Some women experience pruritus during pregnancy, which could be related to skin stretching or cholestasis, a liver condition that occurs during pregnancy.
Symptoms of Chronic Itching
1
Persistent Itching
The itching lasts for six weeks or more, often without a rash.
2
Scratching
Repeated scratching may lead to skin damage, scabs, or infections.
3
Discomfort
Itching that may interfere with sleep and daily activities.
4
Localized or Widespread
Itching can occur on specific areas of the body or be widespread.
Mechanism of Healing
1
Histamine Release
Inflammatory cells release histamines in response to allergens, irritants, or other triggers, causing itching.
2
Neurological Pathways
Itching can also arise from nerve damage or altered neurological pathways in the skin.
3
Skin Healing
Continuous scratching can lead to secondary skin damage (scratching lesions), which heals by typical wound-healing mechanisms, though scratching prolongs the healing process.
Treatment of Chronic Itching
For Skin Conditions
Moisturizers, topical steroids, antihistamines, and corticosteroids are used to treat skin conditions that cause itching.
For Systemic Causes
Treating the underlying disease, such as kidney disease, liver disorders, or thyroid imbalances, may resolve chronic itching.
Neurological Causes
Gabapentin, pregabalin, and antidepressants (SSRIs) are often prescribed for neuropathic itching.
Behavioral Therapies
Stress management techniques, cognitive-behavioral therapy (CBT), and habit-reversal training can be beneficial.
Topical Treatments and Light Therapy
Topical Treatments
Calamine lotion, menthol or pramoxine creams, and capsaicin cream offer relief from itching.
Light Therapy (Phototherapy)
UV light can be effective in treating itch caused by certain skin conditions, including eczema and psoriasis.
Wound Care and Prevention
1
Avoid Scratching
Use cool compresses and anti-itch creams to reduce the urge to scratch.
2
Keep Skin Moisturized
Use thick emollient creams to keep the skin hydrated and prevent further damage.
3
Use Sterile Bandages
If the skin has broken due to scratching, clean the area and cover it with sterile bandages to prevent infection.
4
Topical Antibiotics
If an infection occurs, use a topical antibiotic cream to prevent or treat the infection.
