Pruritus, the medical term for itching, is a sensation that provokes the desire to scratch. It is a common symptom experienced by people of all ages and can range from mild and intermittent to severe and persistent, significantly impacting quality of life. While occasional itching is usually harmless, persistent or severe pruritus can be a sign of an underlying medical condition.
Pruritus is defined as an unpleasant sensation on the skin that elicits the urge to scratch. It is not a disease in itself but rather a symptom that can arise from a wide array of underlying conditions affecting the skin or other bodily systems. The intensity and location of pruritus can vary greatly. It can be localised to a specific area, such as a limb or the scalp, or it can be generalised, affecting the entire body.
The duration of pruritus can also vary, from acute, lasting for a short period, to chronic, persisting for six weeks or longer. Chronic pruritus can be particularly bothersome, interfering with sleep, concentration, and overall well-being.
The mechanisms that cause the sensation of itch are still being actively researched, but it is known to involve specific nerve fibres in the skin that transmit signals to the brain, distinct from those that transmit pain.
Studies estimate that the lifetime prevalence of chronic pruritus (lasting more than six weeks) ranges from 8% to 16% in the adult population globally. The prevalence tends to increase with age. Acute pruritus is even more widespread, affecting a significant portion of the population at some point in their lives, often due to transient skin irritations or insect bites.
Pruritus can be classified based on several factors:
Underlying Cause: This is the most clinically relevant classification:
Distribution:
Duration:
The causes of pruritus are diverse and can be broadly categorised as dermatological, systemic, neurological, and psychogenic:
Dermatological Causes (Skin Conditions):
Systemic Causes (Underlying Medical Conditions):
Neurological Causes (Nerve-Related Issues):
Psychogenic Causes (Psychological Factors):
Other Causes:
Diagnosing the underlying cause of pruritus can be challenging and often requires a thorough evaluation:
The primary goal of pruritus treatment is to identify and address the underlying cause whenever possible. Symptomatic relief is also crucial to improve the patient's comfort and quality of life. Treatment strategies may include:
Treating the Underlying Cause:
If the pruritus is due to a skin condition (e.g., eczema, psoriasis, scabies), systemic disease (e.g., liver disease, kidney disease), or medication side effect, treating the primary condition or discontinuing the offending drug is essential.
Topical Treatments:
Systemic Medications:
Phototherapy (Light Therapy):
Ultraviolet B (UVB) phototherapy can be helpful for pruritus associated with certain skin conditions like psoriasis and eczema.
Other Measures:
"It's Just Dry Skin."
While dryness can cause itch, pruritus can stem from various underlying conditions.
"Scratching Helps."
Scratching provides temporary relief but can worsen the condition.
"Only Skin Diseases Cause Itch."
Systemic diseases can also manifest as pruritus.
It's important to see a doctor for pruritus in the following situations:
When you see your doctor about pruritus, consider asking the following questions:
Pruritus, or itchy skin, is a common and often bothersome symptom with a wide range of potential causes. While occasional itching is usually benign, persistent or severe pruritus can significantly impact quality of life and may indicate an underlying medical condition. Thorough evaluation by a healthcare professional is crucial for accurate diagnosis and appropriate management.