Check when potion expires?

How can I check when a potion effect expires?
I need to add back the potion effects the players given the effect had before the effect was given.

Code:

Code:

        if(item.getType() == Material.SUGAR) {
            p.sendMessage(ChatColor.translateAlternateColorCodes('&', "&6&m--*--------------*--"));
            p.sendMessage(ChatColor.translateAlternateColorCodes('&', "&bSpeed &e» "));
            p.sendMessage(ChatColor.translateAlternateColorCodes('&', "&9Clickable&7: &bSpeed II &7(6s)"));
            p.sendMessage(ChatColor.translateAlternateColorCodes('&', "&9Energy Cost&7: &f40"));
            p.sendMessage(ChatColor.translateAlternateColorCodes('&', "&6&m--*--------------*--"));
            for (Entity all : p.getNearbyEntities(15.0, 15.0, 15.0)) {
                if(p != all && faction != null && faction.getOnlinePlayers().contains(all) && !((Player) all).hasPotionEffect(PotionEffectType.SPEED)) {
                    ((Player) all).addPotionEffect(new PotionEffect(PotionEffectType.SPEED, 100, 1));
                }

 

The effect will be updated tho, so if you have it, you can get more time, so a timer wouldnt work

 

I need to be able to rollback the potion effects a player had. If a special player holds sugar it will give the players around them speed for example. if the player already has speed and it's given, the original speed will get removed. You can hold the sugar again tho, and it will continue giving players speed. After it's run out I want to give back the effects the player had before. Sry for bad explenation