Chloroquine/Hydroxychloroquine Toxicity Follow-up

  • Author: Manolette R Roque, MD, MBA; Chief Editor: Hampton Roy Sr, MD   more...
 
Updated: Jan 21, 2011
 

Further Outpatient Care

Once retinal toxicity is identified, the drug is discontinued; the patient is administered other immunosuppressive agents. Chloroquine and/or hydroxychloroquine clear very slowly from the body, so the full effects may not manifest for 3-6 months. Slow, continued deterioration of visual function may occur even after the drug is discontinued. The authors recommend that patients be reevaluated 3 months after a diagnosis of toxicity is made, even after discontinuation of drug use. Annual examinations are recommended until the findings are clearly stable.

A yearly visual field examination is useful to detect charges from hydroxychloroquine. A small case series study revealed evidence of retinal toxicity that included difficulty with reading, variation in fundus findings from normal to bull’s eye maculopathy, ERG findings of reduced rod and cone function, and abnormal visual fields.[4] Cessation of the study drug did not result in sustained improved visual function. Six of sixteen patients had progressive loss of retinal function despite cessation of the study drug. Chloroquine and hydroxychloroquine are associated with substantial retinal toxicities that require diligent monitoring and management. More sophisticated monitoring is needed when striving for a reduction in retinopathy while maintaining the delivery of good care to patients with rheumatologic disease. Thus, multifocal ERG assessment must become a required element in the preferred practice pattern of patients treated with antimalarial agents.

  • Distance and near acuity
  • Color vision
  • Visual field examination (red pin and red Amsler grid)
  • Slit lamp biomicroscopic examination of the cornea
  • Dilated examination of the retina
  • Electroretinogram (full field and multifocal)
  • Perimetry (Humphrey 10-2)
  • Fundus photography
  • Fluorescein angiography
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Inpatient & Outpatient Medications

Discontinue use of quinolones.

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Deterrence/Prevention

The recommended safe threshold dose has been reported as 3.5 mg/kg/d for chloroquine and 6.5 mg/kg/d for hydroxychloroquine. These dosages are based on lean body weight. A body mass index calculator used by endocrinologists is helpful in calculating the recommended dose.

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Complications

See Physical.

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Prognosis

  • If the maximum daily dosage recommendations are followed, then the likelihood of toxicity is small.
  • If diagnosed early, toxicity (eg, corneal epithelial changes, loss of normal foveal reflex) is reversible.
  • Once the appearance of a bull's eye maculopathy is noted, disturbances associated with this condition are irreversible.
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Patient Education

  • Monitor patients on an annual basis. Record visual symptomatology, visual acuity, and Amsler grid testing.
  • Advise patients to discontinue treatment and to seek consultation with an ophthalmologist if changes in visual acuity or blurred vision occur while on treatment.
  • See Deterrence/Prevention.
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Contributor Information and Disclosures
Author

Manolette R Roque, MD, MBA  General Manager, Full Partner, Ophthalmic Consultants Philippines Co.; President and CEO, Chief Refractive Surgeon, EYE REPUBLIC Ophthalmology Clinic; Section Chief, Ocular Immunology and Uveitis, Department of Ophthalmology, Asian Hospital and Medical Center; Section Chief, Ocular Immunology and Uveitis, International Eye Institute, St Luke's Medical Center Global City; Senior Eye Surgeon, The LASIK Surgery Clinic; Director, AMC Eye Center, Alabang Medical Center; President, Philippine Ocular Inflammation Society

Manolette R Roque, MD, MBA is a member of the following medical societies: American Academy of Ophthalmic Executives, American Academy of Ophthalmology, American Society of Cataract and Refractive Surgery, American Society of Ophthalmic Administrators, American Uveitis Society, International Ocular Inflammation Society, Philippine Medical Association, Philippine Ocular Inflammation Society, and Philippine Society of Cataract and Refractive Surgery

Disclosure: Nothing to disclose.

Coauthor(s)

Barbara L Roque, MD  Full Partner, Ophthalmic Consultants Philippines Co; Service Chief, Pediatric Ophthalmology and Strabismus, Department of Ophthalmology, Asian Hospital and Medical Center; Active Staff, International Eye Institute, St Luke's Medical Center Global City; Visiting Ophthalmologist, AMC Eye Center, Alabang Medical Center

Barbara L Roque, MD is a member of the following medical societies: American Academy of Ophthalmology, American Association for Pediatric Ophthalmology and Strabismus, American Society of Cataract and Refractive Surgery, Philippine Academy of Ophthalmology, and Philippine Society of Cataract and Refractive Surgery

Disclosure: Nothing to disclose.

C Stephen Foster, MD, FACS, FACR, FAAO  Clinical Professor of Ophthalmology, Harvard Medical School; Consulting Staff, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary; Founder and President, Ocular Immunology and Uveitis Foundation, Massachusetts Eye Research and Surgery Institution

C Stephen Foster, MD, FACS, FACR, FAAO is a member of the following medical societies: Alpha Omega Alpha, American Academy of Ophthalmology, American Association of Immunologists, American College of Rheumatology, American College of Surgeons, American Federation for Clinical Research, American Medical Association, American Society for Microbiology, American Uveitis Society, Association for Research in Vision and Ophthalmology, Massachusetts Medical Society, Royal Society of Medicine, and Sigma Xi

Disclosure: Nothing to disclose.

Specialty Editor Board

Kilbourn Gordon III, MD, FACEP  Urgent Care Physician

Kilbourn Gordon III, MD, FACEP is a member of the following medical societies: American Academy of Ophthalmology and Wilderness Medical Society

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD  Senior Pharmacy Editor, eMedicine

Disclosure: eMedicine Salary Employment

J James Rowsey, MD  Former Director of Corneal Services, St Luke's Cataract and Laser Institute, Florida

J James Rowsey, MD is a member of the following medical societies: American Academy of Ophthalmology, American Association for the Advancement of Science, American Medical Association, Association for Research in Vision and Ophthalmology, Florida Medical Association, Pan-American Association of Ophthalmology, Sigma Xi, and Southern Medical Association

Disclosure: Nothing to disclose.

Lance L Brown, OD, MD  Ophthalmologist, Affiliated With Freeman Hospital and St John's Hospital, Regional Eye Center, Joplin, Missouri

Disclosure: Nothing to disclose.

Chief Editor

Hampton Roy Sr, MD  Associate Clinical Professor, Department of Ophthalmology, University of Arkansas for Medical Sciences

Hampton Roy Sr, MD is a member of the following medical societies: American Academy of Ophthalmology, American College of Surgeons, and Pan-American Association of Ophthalmology

Disclosure: Nothing to disclose.

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A 53-year-old female with a complaint of something "funny" with her vision. The possibility of hydroxychloroquine toxicity was entertained, although clinical evidence was not found. Color vision testing and funduscopic examination were normal. A full field electroretinogram was normal, but foveal cone electroretinograms were reduced bilaterally. These findings prompted the question of possible early hydroxychloroquine retinopathy.
Fluorescein angiogram of left macula in patient with hydroxychloroquine retinopathy. Reprinted from American Journal of Ophthalmology, Vol 104, Johnson and Vine, Hydroxychloroquine therapy in massive total doses without retinal toxicity, pages 139-144, Copyright 1987, with permission from Elsevier Science.
Membranous cytoplasmic bodies in ganglion cell of retina. (N=nucleus) (X12,500.) Reprinted from American Journal of Ophthalmology, Vol 67, Gleiser CA, Dukes TW, Lawwill T, Read WK, Bay WW, Brown RS. Ocular changes in swine associated with chloroquine toxicity, pages 399-405, Copyright 1969, with permission from Elsevier Science.
Swollen ganglion cells with foamy cytoplasm (Hematoxylin-eosin, X500). Reprinted from American Journal of Ophthalmology, Vol 67, Gleiser CA, Dukes TW, Lawwill T, Read WK, Bay WW, Brown RS. Ocular changes in swine associated with chloroquine toxicity, pages 399-405, Copyright 1969, with permission from Elsevier Science.
The same patient as described in the image above (other eye, left eye). The patient (with foveal cone electroretinogram reduction) had abnormal computerized acuity mapping of the macula results.
An Amsler grid is used to assess the central portion of the macula. This simple test is helpful for patients to monitor their vision at home.
 
 
 
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