Malegra 100 mg contains sildenafil 100 mg, it can cause temporary visual effects because sildenafil also affects PDE6, an enzyme involved in retinal light processing. D DailyMed +1 Possible effects include: Blue/green or altered color perception Increased sensitivity to light Blurred vision Temporary changes in visual perception These effects are generally mild and transient. In clinical trials, abnormal vision was reported more often with the 100-mg dose than with lower doses. D DailyMed More importantly: sudden loss or marked reduction of vision in one or both eyes is a medical emergency. Sildenafil has been associated temporally with rare cases of NAION, a condition that can cause permanent vision loss. If this happens, stop sildenafil and seek immediate medical attention. D DailyMed +1 If you tell me what vision symptom you experienced after Malegra 100 mg and how long it lasted, I can explain whether it sounds like a typical temporary effect or something requiring urgent evaluation.