Nonmedicinal Ingredients in Topical Corticosteroids Available in Canada.

Background: Nonmedicinal ingredients in topical corticosteroids might exacerbate pre-existing conditions in patients with contact allergies. In Canada, no database exists to help the clinician identify rapidly the ingredients in a topical product. Thus, prescribing topical corticosteroids to patients with contact allergies represents a challenge.
Objectives: This study aimed to identify potential allergens contained in topical corticosteroids available in Canada.
Methods: Ingredients from 140 topical corticosteroids available in Canada were compiled. Ingredients with stronger allergenic potential were identified.
Results: The most frequent potential allergens found in topical corticosteroids were propylene glycol (42.9%) and parabens (27.9%). Chlorocresol was listed in 11.4% of topical corticosteroids, mostly in high potency products. Formaldehyde releasers were also found in 7.1% of topical products.
Conclusions: This study confirms that ingredients in topical corticosteroids may be the cause of recalcitrant dermatitis in certain patients with contact allergies. Prescribing an adapted topical corticosteroid to patients with allergies is primordial in order to ensure optimal care.