Chlorpromazine Chloroquine

From time to time, drug names are confused and the wrong drug is prescribed or dispensed instead of the one intended. Of all the errors that occur, sulfonylureas are often implicated (158). Examples include chlorpropamide instead of chlorpromazine, chloroquine or etodolac instead of chlorpropamide, glyburide instead of thyroxine, and oxybutynin hydrochloride or acetohexamide instead of acetazolamide (SEDA-16, 490 SEDA-17, 495 SEDA-18, 414 SEDA-19, 395 SEDA-21, 443). 

Eye. Several drugs have an affinity for the retinal pigment melanin and thus may accumulate in the eye. Chlorpromazine and other phe-nothiazines bind to melanin and accumulate in the uveal tract, where they may cause retino-toxicity. Chloroquine concentration in the eye can be approximately 100 times that found in the liver. 

For instance, blurring of vision and diplopia are caused by the use of imipramine, iproniazid, chlorpromazine, thioridazine, and promethazine. Impairment of visual acuity is caused by chlorpropamide, tolbutamide, alcohol, chlorpromazine, phenylbutazone, indomethacin, chloroquine, sulfonamides, ethambutol, chloramphenicol, isonex, clioquinol, quinine, streptomycin, and paraaminosalicylate. Yellow vision (xanthopsia) has been traced to the use of sulfonamides, streptomycin, methaqualone, barbiturates, chlorothiazide,... 

The suggestion that congenital cataract (due to denaturation of lens protein) might be due to drugs has some support in man. Chloroquine and chlorpromazine are concentrated in the fetal eye. Since both can cause retinopathy it would seem wise to avoid them in pregnancy if possible. 

Pharmaceuticals Chloroquine sulfate, benzocaine, chlorpromazine, cytosine arabinoside, 4,7-dichloroquinoline, 2,6-dichloropurine, streptomycin, neomycin, vincamine tartarate, 2[4(5) methyl-5(4) imidazolyl-methyl-thio] C13 pyritinol hydrochloride... 

Clinically important, potentially hazardous interactions with acetazolamide, aminoglycosides, anticholinesterases, bambuterol, calcium channel blockers, chloroquine, chlorpromazine, clindamycin, d-pencillamine, ecothiophate iodine, enflurane, furosemide, halothane, hexomethonium, isoflurane, ketamine, lidocaine, lincomycin, lithium salts, magnesium salts, mannitol, MAO inhibitors, organophosphates, pancuronium, phenytoin, polymyxins, procainamide, quinidine, sevoflurane, spectinomycin, tetracyclines... 

Analysis of experimental data from binding studies of chloroquine, chlorpromazine, paraquat, and Nr using Scatchard plots support the concept of more than one binding site participating in these processes (343). 

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