Can you orally ingest a suppository?

Since that is the wrong end of your digestive system, you will not get the results you were expecting. Many medicines are made as suppositories and some of those are intended to have local effect. Some depend on proper use to deliver the active ingredient at a predictable rate and some active ingredients will be destroyed by digestion. There is really no way to predict the outcome other than to say you should follow the instructions for best results.

Depends on what its used to treat. You can take a vaginal suppository that treats yeast infections on suck on it to treat yeast infection in the mouth and throat which was used in HIV treatment and worked on all patients. The problem with using it for other uses is your stomach acid will break it down. And it won't be absorbed in the colon.