Occupational allergic contact dermatitis due to thioureas.

Thioureas are used as additives in rubber products and as antidegradants for natural rubber latex. They are an uncommon cause of allergic contact dermatitis. This case represents an example of occupational allergic contact dermatitis solely from thioureas in rubber products and no cross-reactivity with other rubber allergens. Standard patch tests may fail to detect thiourea-induced allergic contact dermatitis, so clinicians should consider thiourea sensitization in rubber allergy.