Which coin did you buy at ATH? You can stoploss or hold to new ATH (if it is a good coin) 
PRL, EXLIX, XSPEC.
A sincere advice is to HODL and don't panic. There are many who have bought at ATH and are badly struck right now. I recommend averaging your buying price, as rates right now are very low. Don't sell your tokens at cheap rates, you will repent in future.