Horner Syndrome: Pharmacologic Diagnosis

Horner syndrome describes the constellation of findings associated with a lesion affecting the oculosympathetic pathway. Clinically, ipsilateral miosis, ptosis, and anhidrosis form the classic triad, with other features potentially being present.

Without getting into too much detail about the sympathetic pathways and differential diagnosis of Horner syndrome (those will be covered in other articles), I will attempt to highlight the 3 pharmaceutical agents used in the diagnosis of Horner syndrome, discuss the tests, and point out the key ideas that often find themselves in tests.

Hydroxychloroquine And Chloroquine Screening (2016 AAO Recommendations)

The American Academy of Ophthalmology released an updated set of screening recommendations for hydroxychloroquine (Plaquenil) and chloroquine to account for the many studies that have shown the effects of these medications on the retina (1).  It succinctly makes the case for screening, and outlines the evidence for screening methods and parameters to know for screening.

Adverse Effects Of Select Medications

I admit, this one may be a bit more ambitious than is possible to cover in the span of just one article. Obviously, there are TONS of medications, many of them with very vague side effects. Throughout your career you will most likely see many people referred by another doctor for an eye exam because they were placed on a medication that listed "blurred vision" or "eye problem" as a side effect. Your patients may ask you about this. You also may prescribe some medications that need systemic monitoring. While the OKAP probably won't quiz you over some obscure side effect of some uncommonly used medication, there are definitely some ophthalmic and systemic side effects that we need to know very well. While I will try to discuss the salient points in a coherent manner, detailed information will have to be addressed in other articles. This article will also have overlapping information with the Fundamentals section.