diff --git a/src/dropdown/dropdown.component.ts b/src/dropdown/dropdown.component.ts
index 9cc20c02..c64acd19 100644
--- a/src/dropdown/dropdown.component.ts
+++ b/src/dropdown/dropdown.component.ts
@@ -22,7 +22,8 @@ import {
   SimpleChanges,
 } from '@angular/core';
 import { AbstractControl, ControlValueAccessor, FormBuilder, NG_VALUE_ACCESSOR, Validator, FormControl } from '@angular/forms';
-import { Subject } from 'rxjs/Rx';
+import { Subject } from 'rxjs/Subject';
+import 'rxjs/add/operator/takeUntil';
 
 const MULTISELECT_VALUE_ACCESSOR: any = {
   provide: NG_VALUE_ACCESSOR,