It is speculated to be a polymer consisting of thianthrene and phenothiazine subunits. Chemically, it is classified as a piperazinyl phenothiazine. Xylazine is very similar to drugs such as phenothiazine, tricyclic antidepressants, and clonidine. Fluphenazine is a typical antipsychotic of the phenothiazine class. Phenothiazine is converted by the body into the photodynamic compound phenothiazine sulfoxide. Methylene blue is a formal derivative of phenothiazine. It is of the phenothiazine chemical class. Thiethylperazine (Torecan) is an antiemetic of the phenothiazine class. It is in the phenothiazine family of medications. It is structurally related to the phenothiazine derivative veterinary drug "acepromazine". The clinical pharmacology of acepromazine is similar to that of other phenothiazine derived anti-psychotic agents. Triflupromazine (Vesprin) is an antipsychotic medication of the phenothiazine class. The dye is structurally related to methylene blue, which also features a phenothiazine core. Mequitazine (trade name Primalan) is an H antagonist and anticholinergic of the phenothiazine chemical class. Phenobarbital and atropine in combination, an active control substance for phenothiazine research.