i must agree with remedie choice bry. in reguards potency; the low ones are used for acute symptoms and repeated , (6c,30c) the higher ones for verry exper. homeopaths if you make a mistake the aggravation due to high potency can be too much to handle. the really high potency's like 1m,10m,50m are for mental, emotional symptoms, LM is sometimes save to use for a non homeopath due to its powers lasting one day. needs repeating often.but i know in an emergency situation any potency will do. (example in an emergency kit)