It ok to use some kind of rewetting drops or artificial tears? Any better therapy?

Preservative effects. Artificial tears are very safe and don't result in inhibition of your normal tearing. Prolonged use of artificial tears can result in sensitivity to the preservatives causing redness, irritation and burning when dropping them in. Preservative free tears are available. An ophthalmologist can plug your tear drains to preserve your natural tears. Omega 3's are also good for tear production.