- Chemical Irritants: Direct contact with irritants like acids, alkalis, or solvents can cause localized erythema. - Allergic Reactions: Exposure to allergens such as poison ivy or certain medications can lead to erythematous reactions. - Photosensitivity: Some drugs and chemicals can cause skin reactions when exposed to sunlight, resulting in erythema. - Systemic Toxins: Ingestion or absorption of toxins can cause systemic erythema as part of a larger toxic response.
