diff --git a/var/spack/repos/builtin/packages/py-grpcio-tools/package.py b/var/spack/repos/builtin/packages/py-grpcio-tools/package.py
index e2cc8d79db6..e1fd541b47b 100644
--- a/var/spack/repos/builtin/packages/py-grpcio-tools/package.py
+++ b/var/spack/repos/builtin/packages/py-grpcio-tools/package.py
@@ -41,8 +41,10 @@ def setup_build_environment(self, env):
 
         for dep in self.spec.dependencies(deptype="link"):
             query = self.spec[dep.name]
-            env.prepend_path("LIBRARY_PATH", query.libs.directories[0])
-            env.prepend_path("CPATH", query.headers.directories[0])
+            for p in query.libs.directories:
+                env.prepend_path("LIBRARY_PATH", p)
+            for p in query.headers.directories:
+                env.prepend_path("CPATH", p)
 
     def patch(self):
         if self.spec.satisfies("%fj"):
diff --git a/var/spack/repos/builtin/packages/py-grpcio/package.py b/var/spack/repos/builtin/packages/py-grpcio/package.py
index 8a185d48026..8f319edd725 100644
--- a/var/spack/repos/builtin/packages/py-grpcio/package.py
+++ b/var/spack/repos/builtin/packages/py-grpcio/package.py
@@ -55,8 +55,10 @@ def setup_build_environment(self, env):
 
         for dep in self.spec.dependencies(deptype="link"):
             query = self.spec[dep.name]
-            env.prepend_path("LIBRARY_PATH", query.libs.directories[0])
-            env.prepend_path("CPATH", query.headers.directories[0])
+            for p in query.libs.directories:
+                env.prepend_path("LIBRARY_PATH", p)
+            for p in query.headers.directories:
+                env.prepend_path("CPATH", p)
 
     def patch(self):
         filter_file("-std=gnu99", "", "setup.py")