I dont think that it is a time to panic. Due to the volatile nature of Bitcoin,its market face many ups and downs and if there is a huge drop in its price then without any doubt the market will recover soon.So by not doing the mistake of becoming a panic seller we should hold our bitcoins and we should consider this price drop as an opportunity to buy some more bitcoins at lower rates  because in future the price will surely rise again and we will get huge profits.