Plaquenil therapy

You will have been prescribed this drug to treat inflammation of the joints, soft tissues or skin. The drug is usually very well tolerated, but rarely the drug can affect the central vision. These changes usually occur in people who have been taking the drug for five years or more and those on high doses.  Problems occur more frequently in those with a high Body Mass Index (BMI) – overweight individuals.  In the very small number of patients affected this has usually been a permanent change.

Please be aware that these complications are EXCEEDINGLY rare – I have never seen a case despite monitoring many hundreds of people taking the drug.

Typically the changes involve the central vision and will be most noticed when reading. There may be patches of vision missing, loss of colour vision and/or distortion.

  • As part of the process of monitoring the vision you should test with an Amsler chart every month. You should wear your reading glasses and test one eye at a time. With one hand hold the chart at 1 foot (30cm) from your eye and with the other hand cover the other eye. Focus on the central dot. If you notice distortion or bits missing you should report this to your treating doctor.

Amsler Chart

You can download and print off an amsler chart from this link.

  • If you have difficulty with an Amsler chart, you can try reading newspaper print with your reading glasses. You should be able to read the normal print (smaller than headlines and titles).
  • Monitor your colour vision by comparing the colours in each eye separately.  If there is a “washing out” of colour you should have this investigated.

There are other (much more common) causes of reduced and distorted vision that may need to be excluded. A good start would be to see your optometrist to see if the vision defect can be corrected with glasses. If this is not the case you will be referred on to the ophthalmologist.

You can print off an Amsler chart from this site, but please note you do not have Age Related Macular Disease, and you will just be using this chart for monitoring for the toxic effects of Plaquenil.

There is a characteristic Bull’s eye appearance both on direct photography
and following a fluorescein angiogram.