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Hyabak® Hypotonic Sodium Hyaluronate 0.15% is an ophthalmic solution used to alleviate eye dryness symptoms and lubricate the ocular surface. Sodium cromoglicate drops are used to treat red, watery, itchy eyes caused by allergies such as hay fever. Hypromellose eye drops are also known as "artificial tears". They are used to relieve eye dryness and soreness, particularly where the dryness is caused by a reduced flow of tears. They moisten, soothe and lubricate the surface of the eye.
If you're looking for an ocular lubricant - "artificial tears"- there are a number of over the counter ophthalmic products what will suit your purposes. There's no need for sodium cromoglicate. If you want to continue using Hyabak, you don't need to have it prescribed by a vet. It's available over the counter such as here: https://www.amazon.co.uk/HYABAK-MOISTURISING-LUBRICATING-SOLUTION-CONTACT/dp/B00509DLXY
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