Sir,

We report a case of central serous chorioretinopathy (CSCR) following oral tadalafil (Cialis, Lilly-ICOS LLC) use. A review of the literature found one post-marketing surveillance study in which patients with CSCR showed no increase in prescription exposure to phosphodiesterase type 5 (PDE-5) enzyme inhibitors compared with their age-matched controls.1

Case report

A 51-year-old man with no significant past medical history presented with painless reduced central vision in the left eye of 2 weeks duration. His vision became blurred within 24 h of taking tadalafil for enhanced erectile function. He was on no other medication. Examination revealed visual acuities of 3/24 left and 6/5 right, and a large left serous macular detachment. The patient was asked to discontinue tadalafil. Five days later, his left visual acuity improved to 6/12 and the subretinal fluid reduced (Figure 1).

Figure 1
figure 1

Fundal photographs of both eyes of the patient, 5 days after presentation. (a, b) Colour fundus photographs. (c, d) Fundus fluorescein angiography of the right eye showing an ink blot appearance near the fovea, and of the left eye showing a smoke stack appearance at the macula.

Comment

Our patient had a rapid and dramatic response after commencing and discontinuing tadalafil. This case could be an event of association, but could also be cause and effect, as explained below.

PDE-5 inhibitors modify retinal and choroidal blood flow by their pharmacological effects on the PDE-5 enzyme, which is expressed on retinal and choroidal vasculature. This mechanism involving slowing of choroidal blood flow is also seen in the pathogenesis of CSCR.2 The resultant increased hydrostatic pressure within the choroid affects the ability of the overlying RPE to pump fluid from the retina to the choroid.3

A recent randomised controlled trial showed that when tadalafil was used in therapeutic doses daily for 6 months, there was no adverse significant effect on visual function or ocular anatomy.4 Tadalafil may be used once daily or as needed in doses of 2.5–20 mg. Our patient admitted to taking repeated doses larger than 20 mg to achieve a more desired erectile effect.

This case report highlights that patients should be advised not to exceed the maximum dose of tadalafil. This case also reminds us that patients with CSCR need to be asked a thorough drug history (including recreational drugs); this is perhaps overlooked in this group, who are usually healthy and young.