Chloroquine contraindications

Chloroquine (Aralen) is also used in die treatment of extraintestinal amebiasis (see section on Amebicides). Doxycycline is also used to treat infections caused by Neisseria gonorrhoeae, Treponema pallidum, Listeria monocytogenes, Clostridium, and Bacillus anthracis when penicillin is contraindicated. Quinine also may be used for die prevention and treatment of nocturnal leg cramps. 

Chloroquine is contraindicated in patients with known hypersensitivity. It is a good idea to use chloroquine cautiously in patients with hepatic disease or bone marrow depression and during pregnancy. Children are very sensitive to chloroquine, and the drug should be used with extreme caution in children. 

VLa.2,6. Other antimalarials. Doxycydine (see Section ILb) is a useful and effective short-term prophylactic agent for travellers to chloroquine-resistant areas and can be used as an alternative when mefloquine or proguanil is unavailable or mefloquine is contraindicated. In combination with quinine also tetracycline is used as an antimalarial. 

Hydroxychloroquine is approved for the treatment of both systemic and cutaneous lupus erythematosus. Both chloroquine and quinacrine (Atabrine) are also effective in this skin disease. Low-dose chloroquine is used for the therapy of porphyria cutanea tarda in patients in whom phlebotomy has failed or is contraindicated. Other skin diseases in which the drugs are useful (after sunscreens and avoidance of sun exposure) include polymorphous light eruption and solar urticaria. 

Because the condition is relatively benign and only rarely results in visual symptoms, the development of chloroquine keratopathy does not contraindicate continued use of the medication. If, however, symptoms of glare, halos, or reduced vision bother the patient, consideration may be made to reduction of drug dose in consultation with the prescribing physician. 

The use of proguanil plus atovaquone has been reviewed (14). Neuropsychiatric adverse events were more frequent with mefloquine, whereas other adverse events occurred with similar frequencies as with chloroquine plus proguanil and mefloquine. Proguanil plus atovaquone is contraindicated in severe renal insufficiency. Co-administration of proguanil plus atovaquone with rifampicin is not recommended because of reductions in plasma atovaquone concentrations. 

Kaolin/pectin is an antidiarrheal combination that absorbs fluid, and binds and removes digestive tract irritants. They are used for symptomatic treattnent of diarrhea. Kaopectate (190 mg kaolin/mL and 4.34 mg pectin/mL) is an antidiarrheal agent. By being absorbent, it recovers excess fluid in bowel dysfunction. It is contraindicated in obstructive bowel dysfunction. When used concomitantly, kaolin/pectin may impair absorption of the following drugs antidyski-netics, antimuscarinics (especially atropine), chloroquine. 

Chloroquine is directly toxic to E. histolytica trophozoites and is highly concentrated within the liver, making it effective for amebic liver abscess. It is used only when metronidazole or another nitroimidazole is either contraindicated or unavailable. Chloroquine is not effective against intestinal amebiasis because it only attains low concentrations in the colon patients receiving chloroquine for amebic liver abscess also should receive paromomycin or iodoquinol to eliminate intestinal colonization. 

CJliloroquine is contraindicated in patients witli known hypersensitivity. Precautions and interactions for chloroquine are provided in tlie discussion of tlie dmg in die Antimalatial Dm section. 

Metronidazole given for 10 days is effective as monotherapy in many cases of hepatic abscess and has the dual advantage of being both amebicidal and active against anaerobic bacteria. However, treatment failures can occur and follow-up therapy with chloroquine is highly recommended. Luminal amebicides should also be given to eradicate intestinal infection. Treatment with emetine is contraindicated in patients with a history of cardiac disease. The answer is (D). 

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