Over the last few days I've notice that my cats 3rd eyelid is always showing.

He is regularily (monthly) flead and wormed and is due again on 4th July, eats and drinks loads, got a nice shiney coat runs around like a loon and seems in perfect health.

What could cause this?

This can be a sign of underlying untreated illness and in some cases dehydration can be the cause. How are his stools now?

When the Third eye lid is showing it can be various reasons,

The main reasons are an eye infection or The Cat not producing enough fluid to lubricate the eye.

A trip to your Vets is highly advised, if caught it can be treat quite quickly with anti=biotics and eye drops.

Eyes can go bad really quickly so it will be wise to go to your Vets sooner rather than later.

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