Polyvinyl alcohol

How it works

It acts as a viscous demulcent that increases the stability and retention of the tear film on the ocular surface, reducing surface irritation.

Prescribing in practice

• Where preserved (e.g. benzalkonium chloride-containing) preparations are used frequently or long-term, preservative-related ocular surface toxicity can occur, so preservative-free options are preferred for chronic or frequent use and for soft contact lens wearers.
• May cause transient blurring of vision immediately after instillation.
• Separate administration from other eye drops to avoid washout, instilling other medicated drops first.

Monitoring

Routine laboratory monitoring is not required; review symptom control and ocular surface tolerability at clinical follow-up.

Counselling the patient

• Apply as needed for comfort; vision may blur briefly after each drop.
• If using preserved drops, remove soft contact lenses before instillation unless told otherwise.
• Seek review if eye pain, marked redness or visual changes develop.

Evidence & guidelines

Ocular lubricants are an established first-line measure for dry eye disease as reflected in general ophthalmology guidance.