RESUMEN
The ophthalmologic safety of antimalarial drugs is well established, but absolute safety cannot be assured. Three types of side effects may develop. Corneal deposits and neuromuscular-associated blurred vision are always reversible and therefore benign. Visual loss has occurred in patients with retinopathy. Retinopathy may be divided into true retinopathy and premaculopathy. It is true retinopathy that may be associated with visual loss, while premaculopathy consists of subtle visual field and funduscopic abnormalities. These premaculopathic changes are generally completely reversible with drug discontinuation and have not been shown to progress. Hydroxychloroquine appears safer than chloroquine when currently accepted equivalent doses are used. Fewer than 20 patients with true retinopathy caused by hydroxychloroquine have been reported; more patients have developed true retinopathy when taking chloroquine. The safety profile is most dependent on low daily dose and regular ophthalmologic monitoring. The optimal strategy of ophthalmologic testing has not yet been determined, but visual acuity, funduscopic examination and visual field examination should be monitored. Self-administered ophthalmologic testing with Amsler grids may contribute additional safety but is not a replacement for physician testing.
Asunto(s)
Antimaláricos/efectos adversos , Ojo/efectos de los fármacos , Antimaláricos/farmacocinética , Córnea/efectos de los fármacos , Córnea/metabolismo , Humanos , Unión Neuromuscular/efectos de los fármacos , Retina/efectos de los fármacos , SeguridadRESUMEN
Analysis of all published cases and Food and Drug Administration (FDA) reports of retinopathy attributed to hydroxychloroquine sulfate (Plaquenil) does not reveal any evidence of permanent visual field scotoma occurring when the daily dose is related to body weight and does not exceed 6.5 mg/kg for maintenance therapy. Risk factors of unknown degree may appear at this dosage level only when the duration of treatment exceeds 10 years or when chronic renal insufficiency is present. In the absence of risk factors, annual ophthalmologic examinations and central field testing are recommended because non-drug-related macular diseases commonly occur in the older age group. When risk factors are present, more frequent examinations are indicated. A modified Amsler grid screening test for the central 10 degrees of visual field is described and the participation of the treating physician in the testing program is encouraged to provide maximal medicolegal protection.
Asunto(s)
Hidroxicloroquina/efectos adversos , Retinitis Pigmentosa/inducido químicamente , Peso Corporal , Humanos , Retinitis Pigmentosa/diagnóstico , Factores de RiesgoRESUMEN
Analysis of all published cases and Food and Drug Administration reports of retinopathy induced by hydroxychloroquine did not show any evidence of permanent visual-field scotomas occurring when the daily dose did not exceed 6.5 mg/kg body weight for maintenance therapy. Small risk factors may appear at this dosage level only when the duration of treatment exceeds ten years and/or chronic renal insufficiency is present. Because macular diseases not related to this drug commonly occur in older patients, periodic ophthalmologic examinations and central-field testing are recommended. A modified Amsler grid macular screening test is described, and participation of the treating physician in the testing program is encouraged to provide the maximum medicolegal protection.
Asunto(s)
Hidroxicloroquina/efectos adversos , Enfermedades de la Retina/inducido químicamente , Relación Dosis-Respuesta a Droga , Humanos , Enfermedades de la Retina/diagnóstico , Factores de Riesgo , Pruebas de Visión , Campos VisualesRESUMEN
We do not as yet understand all the mechanisms involved in retinal toxicity. Such risk is lower with hydroxychloroquine than with chloroquine. The risk of true retinopathy rises with duration of therapy. The benefit/risk ratio for hydroxychloroquine is at least equal to or better than that of chloroquine, and when the currently recommended dosages of 400 mg per day of hydroxychloroquine and 250 mg per day of chloroquine are not exceeded, this ratio is medically and ophthalmologically acceptable. The most useful tests to detect retinopathy are ophthalmoscopic and/or photographic observation of the macular area for changes in pigmentation, sensitive central visual field testing, and automated computerized perimeter. These tests can be conducted by the attending physician provided that (1) baseline ophthalmologic studies are done (to exclude pre-existing ocular abnormalities); (2) such studies are conducted every six months thereafter; and (3) the patient with ocular abnormalities is immediately referred to an ophthalmologist for further evaluation, even in the absence of symptoms.