Hate to start the response just like the others, but I can't avoid it - clenbuterol is not a steroid. It is a stimulating asthma drug. Secondly, it is well possible that clenbuterol might cause vision issues because it can surely increase your blood pressure, and in such cases the eyes are usually the first ones to feel these BP spikes, since they have the finnest capilars in them. Stop using clenbuterol ASAP, but do it gradually. Decrease the dosage and stop taking it if you are already experiencing this sort of issues. Besides, clenbuterol can cause a miriad of other side effects, and it does not make really much sense to be using it for fat loss when you have much safer alternatives that will be just as effective.