diff --git a/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcClickboxOverlay.java b/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcClickboxOverlay.java
index 339b74f797..12e1dcec34 100644
--- a/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcClickboxOverlay.java
+++ b/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcClickboxOverlay.java
@@ -30,7 +30,6 @@ import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics2D;
 import java.awt.Polygon;
-import java.util.Map;
 import javax.inject.Inject;
 import net.runelite.api.Client;
 import net.runelite.api.NPC;
@@ -59,16 +58,19 @@ public class NpcClickboxOverlay extends Overlay
 	@Override
 	public Dimension render(Graphics2D graphics)
 	{
-		Map<NPC, String> npcMap = plugin.getHighlightedNpcs();
-		for (NPC npc : npcMap.keySet())
+		for (NPC npc : plugin.getHighlightedNpcs())
 		{
-			renderNpcOverlay(graphics, npc, npcMap.get(npc), config.getNpcColor());
+			renderNpcOverlay(graphics, npc, npc.getName(), config.getNpcColor());
 		}
 
-		for (NPC npc : plugin.getTaggedNpcs())
+		NPC[] npcs = client.getCachedNPCs();
+		for (int npcId : plugin.getNpcTags())
 		{
-			String npcName = npc.getName();
-			renderNpcOverlay(graphics, npc, npcName, config.getTagColor());
+			NPC npc = npcs[npcId];
+			if (npc != null && npc.getName() != null)
+			{
+				renderNpcOverlay(graphics, npc, npc.getName(), config.getTagColor());
+			}
 		}
 
 		return null;
diff --git a/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcIndicatorsPlugin.java b/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcIndicatorsPlugin.java
index 3b0fc692d5..c379efb4a4 100644
--- a/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcIndicatorsPlugin.java
+++ b/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcIndicatorsPlugin.java
@@ -31,19 +31,19 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Map;
 import java.util.Set;
 import javax.inject.Inject;
 import lombok.AccessLevel;
 import lombok.Getter;
 import net.runelite.api.Client;
 import net.runelite.api.NPC;
+import net.runelite.api.events.ConfigChanged;
 import net.runelite.api.events.FocusChanged;
-import net.runelite.api.events.GameTick;
 import net.runelite.api.events.MenuOptionClicked;
+import net.runelite.api.events.NpcDespawned;
+import net.runelite.api.events.NpcSpawned;
 import net.runelite.client.config.ConfigManager;
 import net.runelite.client.input.KeyManager;
 import net.runelite.client.menus.MenuManager;
@@ -82,14 +82,22 @@ public class NpcIndicatorsPlugin extends Plugin
 	@Inject
 	private KeyManager keyManager;
 
+	/**
+	 * NPCs tagged with the Tag option
+	 */
 	@Getter(AccessLevel.PACKAGE)
 	private final Set<Integer> npcTags = new HashSet<>();
 
+	/**
+	 * NPCs tagged due to highlight in the config
+	 */
 	@Getter(AccessLevel.PACKAGE)
-	private final List<NPC> taggedNpcs = new ArrayList<>();
+	private final Set<NPC> highlightedNpcs = new HashSet<>();
 
-	@Getter(AccessLevel.PACKAGE)
-	private Map<NPC, String> highlightedNpcs = new HashMap<>();
+	/**
+	 * Highlight strings from the configuration
+	 */
+	private List<String> highlights = new ArrayList<>();
 
 	private boolean hotKeyPressed = false;
 
@@ -110,16 +118,67 @@ public class NpcIndicatorsPlugin extends Plugin
 	protected void startUp() throws Exception
 	{
 		keyManager.registerKeyListener(inputListener);
+		highlights = getHighlights();
+		rebuildNpcs();
 	}
 
 	@Override
 	protected void shutDown() throws Exception
 	{
 		npcTags.clear();
-		taggedNpcs.clear();
+		highlightedNpcs.clear();
 		keyManager.unregisterKeyListener(inputListener);
 	}
 
+	@Subscribe
+	public void onConfigChanged(ConfigChanged configChanged)
+	{
+		if (!configChanged.getGroup().equals("npcindicators"))
+		{
+			return;
+		}
+
+		highlights = getHighlights();
+		rebuildNpcs();
+	}
+
+	private List<String> getHighlights()
+	{
+		String configNpcs = config.getNpcToHighlight().toLowerCase();
+		if (configNpcs.isEmpty())
+			return Collections.emptyList();
+
+		List<String> highlightedNpcs = Arrays.asList(configNpcs.split(DELIMITER_REGEX));
+		return highlightedNpcs;
+	}
+
+	/**
+	 * Rebuild highlighted npcs
+	 */
+	private void rebuildNpcs()
+	{
+		highlightedNpcs.clear();
+
+		for (NPC npc : client.getNpcs())
+		{
+			String npcName = npc.getName();
+
+			if (npcName == null)
+			{
+				continue;
+			}
+
+			for (String highlight : highlights)
+			{
+				if (WildcardMatcher.matches(highlight, npcName))
+				{
+					highlightedNpcs.add(npc);
+					break;
+				}
+			}
+		}
+	}
+
 	@Subscribe
 	public void onFocusChanged(FocusChanged focusChanged)
 	{
@@ -138,59 +197,36 @@ public class NpcIndicatorsPlugin extends Plugin
 	}
 
 	@Subscribe
-	public void onGameTick(GameTick tick)
+	public void onNpcSpawned(NpcSpawned npcSpawned)
 	{
-		highlightedNpcs = buildNpcsToHighlight();
-		taggedNpcs.clear();
-		if (npcTags.isEmpty() || !config.isTagEnabled())
+		NPC npc = npcSpawned.getNpc();
+		String npcName = npc.getName();
+		if (npcName != null)
 		{
-			return;
-		}
-		for (NPC npc : client.getNpcs())
-		{
-			if (npcTags.contains(npc.getIndex()) && npc.getName() != null)
+			for (String highlight : highlights)
 			{
-				taggedNpcs.add(npc);
+				if (WildcardMatcher.matches(highlight, npcName))
+				{
+					highlightedNpcs.add(npc);
+					break;
+				}
 			}
 		}
 	}
 
+	@Subscribe
+	public void onNpcDespawned(NpcDespawned npcDespawned)
+	{
+		NPC npc = npcDespawned.getNpc();
+		highlightedNpcs.remove(npc);
+	}
+
 	@Override
 	public Collection<Overlay> getOverlays()
 	{
 		return Arrays.asList(npcClickboxOverlay, npcMinimapOverlay);
 	}
 
-	private Map<NPC, String> buildNpcsToHighlight()
-	{
-		String configNpcs = config.getNpcToHighlight().toLowerCase();
-		if (configNpcs.isEmpty())
-			return Collections.EMPTY_MAP;
-
-		Map<NPC, String> npcMap = new HashMap<>();
-		List<String> highlightedNpcs = Arrays.asList(configNpcs.split(DELIMITER_REGEX));
-
-		for (NPC npc : client.getNpcs())
-		{
-			String npcName = npc.getName();
-
-			if (npcName == null)
-			{
-				continue;
-			}
-
-			for (String highlight : highlightedNpcs)
-			{
-				if (WildcardMatcher.matches(highlight, npcName))
-				{
-					npcMap.put(npc, npcName);
-				}
-			}
-		}
-
-		return npcMap;
-	}
-
 	void updateNpcMenuOptions(boolean pressed)
 	{
 		if (!config.isTagEnabled())
diff --git a/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcMinimapOverlay.java b/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcMinimapOverlay.java
index c06399d45f..acacb232b8 100644
--- a/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcMinimapOverlay.java
+++ b/runelite-client/src/main/java/net/runelite/client/plugins/npchighlight/NpcMinimapOverlay.java
@@ -28,8 +28,8 @@ package net.runelite.client.plugins.npchighlight;
 import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics2D;
-import java.util.Map;
 import javax.inject.Inject;
+import net.runelite.api.Client;
 import net.runelite.api.NPC;
 import net.runelite.api.Point;
 import net.runelite.client.ui.overlay.Overlay;
@@ -39,12 +39,14 @@ import net.runelite.client.ui.overlay.OverlayUtil;
 
 public class NpcMinimapOverlay extends Overlay
 {
+	private final Client client;
 	private final NpcIndicatorsConfig config;
 	private final NpcIndicatorsPlugin plugin;
 
 	@Inject
-	NpcMinimapOverlay(NpcIndicatorsConfig config, NpcIndicatorsPlugin plugin)
+	NpcMinimapOverlay(Client client, NpcIndicatorsConfig config, NpcIndicatorsPlugin plugin)
 	{
+		this.client = client;
 		this.config = config;
 		this.plugin = plugin;
 		setPosition(OverlayPosition.DYNAMIC);
@@ -54,15 +56,19 @@ public class NpcMinimapOverlay extends Overlay
 	@Override
 	public Dimension render(Graphics2D graphics)
 	{
-		Map<NPC, String> npcMap = plugin.getHighlightedNpcs();
-		for (NPC npc : npcMap.keySet())
+		for (NPC npc : plugin.getHighlightedNpcs())
 		{
-			renderNpcOverlay(graphics, npc, npcMap.get(npc), config.getNpcColor());
+			renderNpcOverlay(graphics, npc, npc.getName(), config.getNpcColor());
 		}
 
-		for (NPC npc : plugin.getTaggedNpcs())
+		NPC[] npcs = client.getCachedNPCs();
+		for (int npcId : plugin.getNpcTags())
 		{
-			renderNpcOverlay(graphics, npc, npc.getName(), config.getTagColor());
+			NPC npc = npcs[npcId];
+			if (npc != null && npc.getName() != null)
+			{
+				renderNpcOverlay(graphics, npc, npc.getName(), config.getTagColor());
+			}
 		}
 
 		return null;