here is a description of what i suffer from, i get episodes of sickness in which i feel extreme tiredness, confusion, malaise, fatigue, lack of energy and vitality, and here is a key symptom, when i'm feeling like that i get blurred vision, i can't read anything it's all blurry, this usually takes 1 or 2 or 3 days to clear up, i usually resort to sleeping when i'm feeling like that, and as time goes the severity of the symptoms changes until i return to normal feeling again, no blurred vision, no feeling of tiredness, i can just resume my normal life again! another symptom that's persistent in days of sickness and health is frequent urination and sometimes sudden urge!