I found this interesting:

"In this in-vitro model of human erythrocytes, the
potassium channel blockers amiodarone and quinidine
both attenuated fluoride-induced hyperkalemia.
Further in-vivo investigation is required to determine
whether amiodarone can enhance survival in fluoride
poisoning."

http://onlinelibrary.wiley.com/doi/10.1197/aemj.10.2.105/pdf