diff --git a/src/asyncActions.ts b/src/asyncActions.ts
index fa60d6c..94f9f7c 100644
--- a/src/asyncActions.ts
+++ b/src/asyncActions.ts
@@ -4,7 +4,7 @@ import { Dispatch, Action } from 'redux';
 import { IInitSplitSdkParams, IGetTreatmentsParams, IDestroySplitSdkParams, ISplitFactoryBuilder } from './types';
 import { splitReady, splitReadyWithEvaluations, splitReadyFromCache, splitReadyFromCacheWithEvaluations, splitTimedout, splitUpdate, splitUpdateWithEvaluations, splitDestroy, addTreatments } from './actions';
 import { VERSION, ERROR_GETT_NO_INITSPLITSDK, ERROR_DESTROY_NO_INITSPLITSDK, getControlTreatmentsWithConfig } from './constants';
-import { matching, getStatus } from './utils';
+import { matching, getStatus, validateGetTreatmentsParams } from './utils';
 
 /**
  * Internal object SplitSdk. This object should not be accessed or
@@ -108,10 +108,8 @@ export function getTreatments(params: IGetTreatmentsParams): Action | (() => voi
     return () => { };
   }
 
-  // Convert string feature flag name to a one item array.
-  if (typeof params.splitNames === 'string') {
-    params.splitNames = [params.splitNames];
-  }
+  params = validateGetTreatmentsParams(params);
+  const splitNames = params.splitNames as string[];
 
   if (!splitSdk.isDetached) { // Split SDK running in Browser
 
@@ -119,11 +117,11 @@ export function getTreatments(params: IGetTreatmentsParams): Action | (() => voi
 
     // Register or unregister the current `getTreatments` action from being re-executed on SDK_UPDATE.
     if (params.evalOnUpdate) {
-      params.splitNames.forEach((featureFlagName) => {
+      splitNames.forEach((featureFlagName) => {
         client.evalOnUpdate[featureFlagName] = { ...params, splitNames: [featureFlagName] };
       });
     } else {
-      params.splitNames.forEach((featureFlagName) => {
+      splitNames.forEach((featureFlagName) => {
         delete client.evalOnUpdate[featureFlagName];
       });
     }
@@ -147,14 +145,14 @@ export function getTreatments(params: IGetTreatmentsParams): Action | (() => voi
     } else {
       // Otherwise, it adds control treatments to the store, without calling the SDK (no impressions sent)
       // @TODO remove eventually to minimize state changes
-      return addTreatments(params.key || (splitSdk.config as SplitIO.IBrowserSettings).core.key, getControlTreatmentsWithConfig(params.splitNames));
+      return addTreatments(params.key || (splitSdk.config as SplitIO.IBrowserSettings).core.key, getControlTreatmentsWithConfig(splitNames));
     }
 
   } else { // Split SDK running in Node
 
     // Evaluate Split and return redux action.
     const client = splitSdk.factory.client();
-    const treatments = client.getTreatmentsWithConfig(params.key, params.splitNames, params.attributes);
+    const treatments = client.getTreatmentsWithConfig(params.key, splitNames, params.attributes);
     return addTreatments(params.key, treatments);
 
   }
diff --git a/src/constants.ts b/src/constants.ts
index f9ba036..c353fd1 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -42,12 +42,12 @@ export const SPLIT_DESTROY = 'SPLIT_DESTROY';
 export const ADD_TREATMENTS = 'ADD_TREATMENTS';
 
 // Warning and error messages
-export const ERROR_GETT_NO_INITSPLITSDK = '[Error] To use "getTreatments" the SDK must be first initialized with a "initSplitSdk" action';
+export const ERROR_GETT_NO_INITSPLITSDK = '[ERROR] To use "getTreatments" the SDK must be first initialized with a "initSplitSdk" action';
 
-export const ERROR_DESTROY_NO_INITSPLITSDK = '[Error] To use "destroySplitSdk" the SDK must be first initialized with a "initSplitSdk" action';
+export const ERROR_DESTROY_NO_INITSPLITSDK = '[ERROR] To use "destroySplitSdk" the SDK must be first initialized with a "initSplitSdk" action';
 
-export const ERROR_TRACK_NO_INITSPLITSDK = '[Error] To use "track" the SDK must be first initialized with an "initSplitSdk" action';
+export const ERROR_TRACK_NO_INITSPLITSDK = '[ERROR] To use "track" the SDK must be first initialized with an "initSplitSdk" action';
 
-export const ERROR_MANAGER_NO_INITSPLITSDK = '[Error] To use the manager, the SDK must be first initialized with an "initSplitSdk" action';
+export const ERROR_MANAGER_NO_INITSPLITSDK = '[ERROR] To use the manager, the SDK must be first initialized with an "initSplitSdk" action';
 
-export const ERROR_SELECTOR_NO_SPLITSTATE = '[Error] When using selectors, "splitState" value must be a proper splitio piece of state';
+export const ERROR_SELECTOR_NO_SPLITSTATE = '[ERROR] When using selectors, "splitState" value must be a proper splitio piece of state';
diff --git a/src/utils.ts b/src/utils.ts
index dff2aab..1409026 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,3 +1,5 @@
+import { IGetTreatmentsParams } from './types';
+
 /**
  * Validates if a value is an object.
  */
@@ -29,3 +31,78 @@ export function getStatus(client: SplitIO.IClient): IClientStatus {
   // @ts-expect-error, function exists but it is not part of JS SDK type definitions
   return client.__getStatus();
 }
+
+/**
+ * Validates and sanitizes the parameters passed to the "getTreatments" action creator.
+ *
+ * @returns {IGetTreatmentsParams} The returned object is a copy of the passed one, with the "splitNames" property converted to an array of strings.
+ */
+export function validateGetTreatmentsParams(params: IGetTreatmentsParams) {
+  let { splitNames } = params;
+  if (typeof splitNames === 'string') splitNames = [splitNames];
+  if (!validateFeatureFlags(splitNames)) splitNames = [];
+
+  return {
+    ...params,
+    splitNames: splitNames,
+  };
+}
+
+// The following input validation utils are based on the ones in the React SDK. They might be replaced by utils from the JS SDK in the future.
+
+function validateFeatureFlags(maybeFeatureFlags: unknown, listName = 'feature flag names'): false | string[] {
+  if (Array.isArray(maybeFeatureFlags) && maybeFeatureFlags.length > 0) {
+    const validatedArray: string[] = [];
+    // Remove invalid values
+    maybeFeatureFlags.forEach((maybeFeatureFlag) => {
+      const featureFlagName = validateFeatureFlag(maybeFeatureFlag);
+      if (featureFlagName) validatedArray.push(featureFlagName);
+    });
+
+    // Strip off duplicated values if we have valid feature flag names then return
+    if (validatedArray.length) return uniq(validatedArray);
+  }
+
+  console.log(`[ERROR] ${listName} must be a non-empty array.`);
+  return false;
+}
+
+const TRIMMABLE_SPACES_REGEX = /^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/;
+
+function validateFeatureFlag(maybeFeatureFlag: unknown, item = 'feature flag name'): false | string {
+  if (maybeFeatureFlag == undefined) {
+    console.log(`[ERROR] you passed a null or undefined ${item}, ${item} must be a non-empty string.`);
+  } else if (!isString(maybeFeatureFlag)) {
+    console.log(`[ERROR] you passed an invalid ${item}, ${item} must be a non-empty string.`);
+  } else {
+    if (TRIMMABLE_SPACES_REGEX.test(maybeFeatureFlag)) {
+      console.log(`[WARN] ${item} "${maybeFeatureFlag}" has extra whitespace, trimming.`);
+      maybeFeatureFlag = maybeFeatureFlag.trim();
+    }
+
+    if ((maybeFeatureFlag as string).length > 0) {
+      return maybeFeatureFlag as string;
+    } else {
+      console.log(`[ERROR] you passed an empty ${item}, ${item} must be a non-empty string.`);
+    }
+  }
+
+  return false;
+}
+
+/**
+ * Removes duplicate items on an array of strings.
+ */
+function uniq(arr: string[]): string[] {
+  const seen: Record<string, boolean> = {};
+  return arr.filter((item) => {
+    return Object.prototype.hasOwnProperty.call(seen, item) ? false : seen[item] = true;
+  });
+}
+
+/**
+ * Checks if a given value is a string.
+ */
+function isString(val: unknown): val is string {
+  return typeof val === 'string' || val instanceof String;
+}
diff --git a/types/utils.d.ts b/types/utils.d.ts
index 8608b7b..241e116 100644
--- a/types/utils.d.ts
+++ b/types/utils.d.ts
@@ -1,3 +1,4 @@
+import { IGetTreatmentsParams } from './types';
 /**
  * Validates if a value is an object.
  */
@@ -17,3 +18,15 @@ export interface IClientStatus {
     isDestroyed: boolean;
 }
 export declare function getStatus(client: SplitIO.IClient): IClientStatus;
+/**
+ * Validates and sanitizes the parameters passed to the "getTreatments" action creator.
+ *
+ * @returns {IGetTreatmentsParams} The returned object is a copy of the passed one, with the "splitNames" property converted to an array of strings.
+ */
+export declare function validateGetTreatmentsParams(params: IGetTreatmentsParams): {
+    splitNames: string[];
+    key?: import("@splitsoftware/splitio/types/splitio").SplitKey;
+    attributes?: import("@splitsoftware/splitio/types/splitio").Attributes;
+    evalOnUpdate?: boolean;
+    evalOnReadyFromCache?: boolean;
+};