Central serous chorioretinopathy induced by drugs metabolized by cytochrome P450 3A4

The purpose of this study was investigate whether replacing or discontinuing drugs that are inhibitors or substrates of cytochrome P450 3A4 (CYP3A4) may improve the clinical course of central serous chorioretinopathy (CSC). A retrospective observational study included 43 patients with active CSC. Twenty seven patients (32 eyes, group 1) were using drugs that act as substrates or inhibitors of CYP3A4. In 25 of these 27 patients, treatments including steroids, calcium channel blockers, anticoagulants, statins, beta-adrenolytics, angiotensin receptor antagonists, antidepressants, muscarinic receptor antagonists, phosphodiesterase type 5 inhibitors, and others were discontinued or replaced with medications not affecting CYP3A4. Sixteen patients (19 eyes, group 2) not using any medication that affects CYP3A4, were given eplerenone, rifampicin, or laser treatment. Main outcomes measures were assessed by functional and anatomical images obtained using multimodal imaging techniques. The average follow-up time was 12 months. In group I after discontinuing or replacing substrates or inhibitors of CYP3A4, improvements were observed in 18 patients (22 eyes). None of the patients that were using drugs affecting CYP3A4 improved with eplerenone therapy, however, all 18 patients improved after discontinuing the drugs. All these drugs had a blocking effect on eplerenone therapy. Best corrected visual acuity (BCVA) improved in 14 eyes, remained unchanged in 5 eyes, and worsened in 3 eyes. In 21 of the 22 eyes, subretinal fluid absorption was observed with optical coherence tomography (OCT). Mean central retinal thickness decreased from 361 μm to 219 μm. One patient (2 eyes) was unable to change treatment (due to neoplasm), one patient (1 eye) did not agree to change or stop treatment, and seven patients (7 eyes) were lost to follow-up. Of the 16 patients (19 eyes) who were treated with eplerenone, rifampicin, or laser, improvements were observed in 14 patients (16 eyes), two patients (2 eyes) were lost to follow-up, and CSC worsened in 1 eye. We concluded that patients with CSC should not take substrates or inhibitors of CYP3A4. These drugs should be replaced with alternatives that act through other metabolic pathways.