acne produced by external irritants, such as tar (chloracne), or by normally orally administered drugs internally administered, such as iodides or bromides.
A virtually extinct term for any type of acne vulgaris caused by exposure to various chemicals (e.g., acne cosmetica, pomade acne, acne detergicans) or environmental factors (e.g., acne mechanica, acne aestivalis, tropical acne).