Check out this post from The Consumerist about how unhappy the FDA is with Durezol and Durasal.
A hint: It’s ok if you accidentally use Durezol when you wanted Durasal, but the penalty is high for using Durasal instead of Durezol!*
This link contains an explanation of the names:
When drugs are submitted to the FDA for approval, the Agency carefully screens their proprietary names for similarities. However, Durasal (salicylic acid) is an OTC medication that did not undergo the approval process. That is why the two names exist side-by-side in the pharmacies.
Thus far, the FDA is asking pharmacists to “be vigilant.” I think we know how that usually plays out.
*Durezol is eye drops. Durasal is wart remover.