Viscotears Single Dose Units are eye drops which take the form of a liquid gel. They are designed to treat dry and sore eyes, creating ‘artificial tears’ to help to promote hydration in your eyes. Ideal for anyone who suffers with dry and tired eyes. Viscotears Single Dose Units use an active ingredient called carbomer in their liquid gel. They belong to a group of eye drops referred to as ‘artificial tears’, meaning that they treat dryness and irritation by lubricating your eyes, relieving discomfort and itching.