Hi mama, kung okay lang sa OB mo yan then you're good to go, doctors wouldn't clear it if it wasn't safe sa first trimester, kaya relax na! Kremil-S is pretty commonly prescribed para sa acid reflux during pregnancy kaya maraming moms namin ang umiinom nito without issue, pero if you're still nervous, you can always text your OB ulet to ask exactly kung bakit prescribed siya sayo or kung may specific instructions on timing/dosage para ma-ease your mind completely.