You note that the Premarin you’re using several times each week is expensive, and wonder about a nonprescription alternative. It’s the estrogen contained in that treatment that makes it both a successful treatment and available by prescription. The tissues of the vulva and vagina are very receptive to the healing effects of estrogen, and nothing else is equally effective.
Vaginal moisturizers offer benefit to retain moisture especially when the vulva and vagina are healthy; they aren’t able to reverse the atrophy that occurs in menopause. If you’d like to try a vaginal moisturizer, be sure to use it very consistently, two to three times a week.
You can experiment with a moisturizer to see whether it helps to maintain comfort.