diff --git a/index.js b/index.js
index 4358aeb..ba27cc0 100644
--- a/index.js
+++ b/index.js
@@ -12,7 +12,6 @@
  * @private
  */
 
-const isPromise = require('is-promise')
 const Layer = require('./lib/layer')
 const { METHODS } = require('node:http')
 const parseUrl = require('parseurl')
@@ -647,7 +646,7 @@ function processParams (params, layer, called, req, res, done) {
 
     try {
       const ret = fn(req, res, paramCallback, paramVal, key)
-      if (isPromise(ret)) {
+      if (ret instanceof Promise) {
         if (!(ret instanceof Promise)) {
           deprecate('parameters that are Promise-like are deprecated, use a native Promise instead')
         }
diff --git a/lib/layer.js b/lib/layer.js
index 6a4408f..30df225 100644
--- a/lib/layer.js
+++ b/lib/layer.js
@@ -12,7 +12,6 @@
  * @private
  */
 
-const isPromise = require('is-promise')
 const pathRegexp = require('path-to-regexp')
 const debug = require('debug')('router:layer')
 const deprecate = require('depd')('router')
@@ -116,7 +115,7 @@ Layer.prototype.handleError = function handleError (error, req, res, next) {
     const ret = fn(error, req, res, next)
 
     // wait for returned promise
-    if (isPromise(ret)) {
+    if (ret instanceof Promise) {
       if (!(ret instanceof Promise)) {
         deprecate('handlers that are Promise-like are deprecated, use a native Promise instead')
       }
@@ -152,7 +151,7 @@ Layer.prototype.handleRequest = function handleRequest (req, res, next) {
     const ret = fn(req, res, next)
 
     // wait for returned promise
-    if (isPromise(ret)) {
+    if (ret instanceof Promise) {
       if (!(ret instanceof Promise)) {
         deprecate('handlers that are Promise-like are deprecated, use a native Promise instead')
       }
diff --git a/package.json b/package.json
index e6be557..1b1240a 100644
--- a/package.json
+++ b/package.json
@@ -15,7 +15,6 @@
   "dependencies": {
     "debug": "^4.4.0",
     "depd": "^2.0.0",
-    "is-promise": "^4.0.0",
     "parseurl": "^1.3.3",
     "path-to-regexp": "^8.0.0"
   },