Vessel constrictor. Vasocon is an otc vasocontrictor drop, which will temporarily constrict dilated ocular surface blood vessels and make the eye look "whiter". The effect wears off after a few hours, and it may be necessary to use the drops more and more to achieve the desired effect after a time. If your eyes are always irritated and look "bloodshot", it is best to see an eye md for diagnosis and advice.
Use something else. Vasocon is a vasocontrictor which gives you temporary relief but in the long run can irritate your eyes even more. It shrinks your blood vessels on the surface of your eye making them look white. But when you stop, your vessels dilate again. Eventually, you have to keep using them and this leads to chronic irritation. Use regular artificial tears instead.