Which class of topical medication is most likely to cause contact allergic dermatitis?

Aminoglycosides are known to have a higher propensity to cause contact allergic dermatitis compared to other classes of topical medications. This is largely due to their chemical structure, which can elicit immune responses in certain individuals, leading to allergic reactions manifested as dermatitis. Such reactions may occur upon direct contact with the drug, especially if the individual has sensitization to the components of the medication.

In contrast, the other classes listed, such as cephalosporins, prostaglandins, and beta blockers, are less frequently associated with contact dermatitis. While they can cause allergic reactions in general, their topical formulations and mechanisms of action are not as commonly linked to direct contact dermatitis. Cephalosporins, for instance, may cause systemic allergic reactions but are not predominantly associated with topical forms. Prostaglandins are primarily utilized for intraocular pressure reduction in glaucoma and have a different side effect profile that does not commonly include contact dermatitis. Beta blockers applied topically tend to have systemic effects rather than causing localized allergic skin reactions.

The propensity of aminoglycosides for this type of allergic dermatitis makes them the most likely choice among the options provided.