1 In dogs, cetirizine is used primarily to treat allergic symptoms and itchy skin e.g from allergic dermatitis and atopy in dogs.  In cats, cetirizine is used to treat non-responsive chronic inflammation of the nose and sinuses (rhinosinusitis). It is also used to treat pruritus (itching) in cats.
Mother of pearl, also called nacre, is an iridescent layer of material that forms the shell lining of many mollusks. Pearl oysters and abalone are both sources of this substance, which is widely used as an inlay in jewelry, furniture, and musical instruments.
Pearl's lack of a mother is a reference to the phrase mother of Pearl, which Mr. Krabs says when something surprises him. Stephen Hillenburg is against revealing the identity of Mrs. Krabs and has kept it a secret throughout the series.