diff --git a/pinecone/grpc/pinecone.py b/pinecone/grpc/pinecone.py
index b03da15d7..7926afc83 100644
--- a/pinecone/grpc/pinecone.py
+++ b/pinecone/grpc/pinecone.py
@@ -1,5 +1,7 @@
 from pinecone import Pinecone
 from pinecone.config import ConfigBuilder
+from pinecone.utils import normalize_host
+from pinecone.pinecone import check_realistic_host
 from .index_grpc import GRPCIndex
 
 
@@ -122,8 +124,13 @@ def Index(self, name: str = "", host: str = "", **kwargs):
         if name == "" and host == "":
             raise ValueError("Either name or host must be specified")
 
-        # Use host if it is provided, otherwise get host from describe_index
-        index_host = host or self.db.index._get_host(name)
+        if host != "":
+            check_realistic_host(host)
+            # Use host url if it is provided
+            index_host = normalize_host(host)
+        else:
+            # Otherwise, get host url from describe_index using the index name
+            index_host = self.db.index._get_host(name)
 
         pt = kwargs.pop("pool_threads", None) or self._pool_threads
 
diff --git a/tests/unit_grpc/test_grpc_index_initialization.py b/tests/unit_grpc/test_grpc_index_initialization.py
index b0b642505..987728f99 100644
--- a/tests/unit_grpc/test_grpc_index_initialization.py
+++ b/tests/unit_grpc/test_grpc_index_initialization.py
@@ -1,3 +1,4 @@
+import pytest
 import re
 from pinecone.grpc import PineconeGRPC, GRPCClientConfig
 
@@ -73,7 +74,7 @@ def test_config_passed_when_target_by_host(self):
     def test_config_passed_when_target_by_host_and_port(self):
         pc = PineconeGRPC(api_key="YOUR_API_KEY")
         config = GRPCClientConfig(timeout=5, secure=False)
-        index = pc.Index(host="myhost:4343", grpc_config=config)
+        index = pc.Index(host="myhost.example.com:4343", grpc_config=config)
 
         assert index.grpc_client_config.timeout == 5
         assert index.grpc_client_config.secure == False
@@ -83,7 +84,7 @@ def test_config_passed_when_target_by_host_and_port(self):
         assert index.grpc_client_config.conn_timeout == 1
 
         # Endpoint calculation does not override port
-        assert index._endpoint() == "myhost:4343"
+        assert index._endpoint() == "myhost.example.com:4343"
 
     def test_config_passes_source_tag_when_set(self):
         pc = PineconeGRPC(api_key="YOUR_API_KEY", source_tag="my_source_tag")
@@ -91,3 +92,24 @@ def test_config_passes_source_tag_when_set(self):
             re.search(r"source_tag=my_source_tag", pc.db._index_api.api_client.user_agent)
             is not None
         )
+
+    def test_invalid_host(self):
+        pc = PineconeGRPC(api_key="key")
+
+        with pytest.raises(ValueError) as e:
+            pc.Index(host="invalid")
+        assert "You passed 'invalid' as the host but this does not appear to be valid" in str(
+            e.value
+        )
+
+        with pytest.raises(ValueError) as e:
+            pc.Index(host="my-index")
+        assert "You passed 'my-index' as the host but this does not appear to be valid" in str(
+            e.value
+        )
+
+        # Can instantiate with realistic host
+        pc.Index(host="test-bt8x3su.svc.apw5-4e34-81fa.pinecone.io")
+
+        # Can instantiate with localhost address
+        pc.Index(host="localhost:8080")