What is the difference between hydroxyzine hcl and hydroxyzine pam both 25mg?

Just a little: The active ingredient, hydroxyzine is the same in both formualtions, though the salt, pamoate or hydrochloride (hcl), to which it is attached is different. The pamoate comes as a capsule and the hydrochloride is a tablet. The release mechanism into the body is different between the two and therefore one may work better than the other for certain individuals.

None: There is a slight formulation between the 2 compounds. HCL is atarx and the pamoate is vistril. They can and are used interchangeably and have the same side effects. They are made by different companies.