Artificial Tears - Chemistry

Chemistry

Preparations contain carboxymethyl cellulose, hydroxypropyl methylcellulose (a.k.a. HPMC or hypromellose), and hydroxypropyl cellulose. They contain water, salts and polymers but lack the proteins found in natural tears. Patients who use them more frequently than once every three hours should choose a brand without preservatives or one with special non-irritating preservatives.

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