Ive always avoided using medication if possible. One of the best ways to cure ick is simply by raising the water temp to 88-89 degrees for 2 weeks. during this time you can add some sea salt- about 1 teaspoon per 5 gallons of water has worked perfectly in the past. if you can raise the temp slow then leave it there until no white spots can be seen- minimum 2 weeks. salt is a natural and help fish produce more slime which help protect the fish from attack. the salinity in the water also helps destroy the parasites. remember to raise the temp slowly and when treatment is over slowly lower it. during this treatment continue with water changes/gravel vacumming. (i hope you have been a water changer) anyway good luck! Also very important- only use sea salt with no added ingredients- you must read the back label in the grocery store- some have added caking ingrediants- only use pure evaporated sea water. when mixing the salt add it to a glass of tank water to desolve it first then slowly.........add it to the tank.

It does sound like ich. however if you do the treatement like the previous answerer, where it takes 2 weeks, the fish could die. I've seen them die in as little as 2 days with it.
You don't say what meds you're using, but there should be directions on the back label, or if in a box, perhaps there's a directions sheet inside. Most meds are given different and for longer periods, so you need to tell us what ur using in order to answer.

If you are treating for ich follow the directions. Usually 7-14 days depending 21 for salt water. Leave the filter medium out the entire time it isn't needed anyway except to pull medication out of the tank so leave it out.

Water changes and treatment. I do not know what you are using to treat or what kind of fish you are treating. SImple follow the directions. Usually 7-14 days depending

Ok if your fish are dying. They are dying from the ick and not the meds. It is in the late stages i Am guessing. What you can do it attack the ick 3 ways at once. Get some medicated food for your fish. Then get a wide spectrum parasite medication along with a specific ick medication. Be sure that the 2 meds can be used together. Most meds that are made from the same manufacture can be used together. Follow all the directions on the meds labels. Ick is a periste so you need to act fast. And leave out the activated carbon for the whole time you are medicating the tank. The carbon will remove the meds from the water. Be aware that some ick meds require that you raise the temp of your water. Just follow all the direction on the meds.