You can teach at a pharmacy school with just a PharmD. Here's a good source for information about faculty at pharmacy schools. The average salary ranges from ~$70k as an assistant professor up to ~$113k as a full professor. There is currently a bill pending in the Senate that would, among other things, pay up to $35k/year in student loans if you commit to teach at a pharmacy school for a minimum of two years. I wonder how competitive faculty positions are for a PharmD to attain.
You can absolutely teach with a PharmD! You can become a "professor of pharmacy practice". You'll probably have to have completed a residency/fellowship training with a demonstration of "scholarly endeavours", ie., co-authored in journals, etc. My school requires that the professor maintain a clinical practice.