@kathleenandbob, opium tincture is an opioid medication used to treat diarrhea in adults. It's not approved by the FDA, since it's a very old medication that's been "grandfathered" in under the current law. This means it isn't required to go through the same approval process as new medications are today. It is a controlled medication, so there are special requirements to get a prescription filled. This may explain why it isn't widely available any longer.

Since this medication is only available by prescription, have you asked your prescribing doctor where it may be available? Or ask if there might be an equally effective medication to help with diarrhea?