Atopic Dermatitis (Eczema): This is the most common cause of itchy periorbital erythema, especially in individuals with a history of atopy. The skin around the eyes is thin and sensitive, making it prone to irritation and allergic reactions.

Contact Dermatitis: This can be either irritant or allergic in nature. Common allergens include fragrances, preservatives in cosmetics, and certain metals. It presents with erythema, edema, and pruritus in the areas exposed to the offending agent.
Seborrheic Dermatitis: Although it more commonly affects the scalp, face, and torso, seborrheic dermatitis can cause itchy, erythematous patches around the eyes, especially in the medial canthal area.
Allergic Conjunctivitis: This condition often presents with itchy, watery eyes and can be associated with periorbital erythema due to rubbing or the allergic response itself.

Angioedema: Although less common, angioedema can present with sudden onset of periorbital edema and erythema, often accompanied by itching. It can be a part of an allergic reaction and, in severe cases, may involve the respiratory tract, making it potentially life-threatening.
Herpes Zoster (Shingles): When involving the ophthalmic division of the trigeminal nerve, herpes zoster can cause severe pain, erythema, and vesicles around the eye. Itching may precede the rash. Early recognition is crucial to prevent complications like herpes zoster ophthalmicus.

Dermatomyositis: This autoimmune condition can cause periorbital erythema and edema, often with a violaceous hue. Itching may be present, and the condition is associated with muscle weakness.
Granuloma Faciale: A rare, chronic condition characterized by single or multiple, erythematous to brownish, well-demarcated plaques, typically on the face, including the periorbital area. Itching can be a symptom.
Sarcoidosis: Although rare, sarcoidosis can manifest with skin lesions, including erythema and plaques around the eyes, and may be accompanied by itching. Systemic symptoms and other organ involvement are common.