Ask our Experts

A reader asks:

 I am taking St. John’s wort for depression. One of the well-known side effects is photosensitivity. Is this a concern when using a light therapy unit such as the Carex Health Brands or other models that filter out UV radiation?

Answer:

Photosensitization is unusual when it comes to St. John’s Wort. While most photosensitizing meds react to UV (and sometimes also to blue light), St. John’s Wort — hypericum — photosensitizes to green light, right in the middle of the visual spectrum. Here is a case where the drug (or non-prescription “supplement”) should not be combined with bright light therapy, because the light contains a major green component. Since you are asking about adding light therapy to St. John’s Wort, we can guess that the drug is not doing an adequate job on its own. You may want to consider, then, whether light therapy does a better job — but also on its own. In other words, by all means try light therapy, but first discontinue use of St. John’s Wort at least until you make the assessment.