Avoiding Plaquenil in AMD

I received the following question:
Do you still advise that Plaquenil, (hydroxychloroquine) not be used in someone with AMD?

I still advise against it especially if someone has bonafide AMD. There are exceptions to any rule but recent studies have shown that the outer retina is damaged with Plaquenil before we see any visible signs in the fundus or on fluorescein angiography. Lai and colleagues found abnormal multifocal electroretinograms (MERGs) in patients taking Plaquenil who otherwise looked normal. The MERG improved slightly in those who stopped the drug and worsened in those who continued taking it.1 An excellent editorial by Marmor talked about the difficulties in using the finicky MERG to determine if Plaquenil should be stopped.2

This August, Kellner et al. showed autofluorescence abnormalities in the macula before any visible changes. In four patients, the MERG was abnormal even before the autofluorescence.3 Marmor correctly pointed out that the MERG was abnormal in patients who had normal vision and no symptoms.

My point is that hydroxychloroquine is causing changes in the outer retina before we can see any visible damage and these are the same layers that are damaged in AMD. I have no evidence and have done no study, but it seems advisable to avoid this drug if possible in people with AMD.

References

1. Lai TY, Chan WM, Li H, Lai RY, Lam DS: Multifocal electroretinographic changes in patients receiving hydroxychloroquine therapy. American journal of ophthalmology 2005, 140(5):794-807.
   
2. Marmor MF: The dilemma of hydroxychloroquine screening: new information from the multifocal ERG. American journal of ophthalmology 2005, 140(5):894-895.
   
3. Kellner U, Renner AB, Tillack H: Fundus autofluorescence and mfERG for early detection of retinal alterations in patients using chloroquine/hydroxychloroquine. Investigative ophthalmology & visual science 2006, 47(8):3531-3538.