- Itching (Pruritus)
Appearance:
- Red, irritated, or normal-looking skin.
- May develop scratches, rashes, or lesions due to repeated scratching.
Causes:
- Allergies, insect bites, dry skin, eczema, or infections.
- Systemic conditions like liver disease or diabetes.
Physiological Response:
- Activation of nerve fibers (C-fibers) by histamine or non-histaminergic mediators.
- Triggered by irritants, allergens, or inflammation.
Pathological Response:
- Persistent scratching leads to skin damage, infections, or chronic pruritus.
Prevention:
- Maintain hydration and use mild cleansers.
- Avoid allergens and irritants.
Treatment:
- Antihistamines, corticosteroid creams, or moisturizers.
- Erythema (Redness)
Appearance:
- Diffuse redness due to increased blood flow (vasodilation).
- Commonly seen in sunburn, inflammation, or infections.
Causes:
- Irritants, allergens, sun exposure, or skin trauma.
Physiological Response:
- Local vasodilation and increased blood flow in response to injury or irritation.
- Release of inflammatory mediators (prostaglandins, histamine).
Pathological Response:
- Chronic erythema can lead to telangiectasia or persistent redness.
Prevention:
- Use sunscreen and avoid irritants.
- Manage underlying inflammatory conditions.
Treatment:
- Anti-inflammatory creams or soothing agents.
- Pain
Appearance:
- Swelling, redness, or lesions depending on the cause.
Causes:
- Injury, burns, infections, or inflammation.
Physiological Response:
- Activation of nociceptors (pain receptors) due to injury or inflammation.
- Release of prostaglandins, bradykinins, and other mediators.
Pathological Response:
- Chronic pain can lead to hypersensitivity and psychological distress.
Prevention:
- Protect skin from trauma and harsh chemicals.
Treatment:
- Topical analgesics or anti-inflammatory creams.
- Swelling (Edema)
Appearance:
- Puffy, raised area due to fluid accumulation.
Causes:
- Infections, allergic reactions, or trauma.
Physiological Response:
- Increased capillary permeability and fluid leakage into tissues.
- Triggered by histamine, cytokines, or injury.
Pathological Response:
- Prolonged swelling can cause fibrosis or tissue damage.
Prevention:
- Avoid allergens and manage inflammatory conditions.
Treatment:
- Cold compresses or anti-inflammatory agents.
- Inflammation
Appearance:
- Redness, swelling, heat, and pain.
Causes:
- Infection, injury, autoimmune reactions, or irritants.
Physiological Response:
- Release of inflammatory mediators (cytokines, histamines).
- Recruitment of immune cells to the site of injury.
Pathological Response:
- Chronic inflammation leads to tissue damage and scarring.
Prevention:
- Avoid irritants and treat infections promptly.
Treatment:
- Anti-inflammatory creams or oral medications.
- Pustule
Appearance:
- Raised, inflamed bump filled with pus.
- Common in acne or infections.
Causes:
- Bacterial infections (e.g., Staphylococcus).
- Blocked pores or hair follicles.
Physiological Response:
- Immune response to infection causes pus formation.
- Increased white blood cell activity at the site.
Pathological Response:
- Untreated pustules may lead to scarring or spread of infection.
Prevention:
- Keep skin clean and avoid picking at blemishes.
Treatment:
- Antibacterial creams or oral antibiotics.