diff --git a/packages/api/src/directives.ts b/packages/api/src/directives.ts
index fd54cbb66..435166539 100644
--- a/packages/api/src/directives.ts
+++ b/packages/api/src/directives.ts
@@ -1,32 +1,41 @@
-import { mapSchema, getDirective, MapperKind } from '@graphql-tools/utils'
+import { getDirective, MapperKind, mapSchema } from '@graphql-tools/utils'
 import { GraphQLNonNull, GraphQLScalarType, GraphQLSchema } from 'graphql'
 import { SanitizedString } from './scalars'
 
 export const sanitizeDirectiveTransformer = (schema: GraphQLSchema) => {
   return mapSchema(schema, {
     [MapperKind.FIELD]: (fieldConfig) => {
-      const sanitizeDirective = getDirective(schema, fieldConfig, 'sanitize')
-      if (!sanitizeDirective || sanitizeDirective.length < 1) {
+      const sanitizeDirective = getDirective(
+        schema,
+        fieldConfig,
+        'sanitize'
+      )?.[0]
+      if (!sanitizeDirective) {
         return fieldConfig
       }
 
-      const maxLength = sanitizeDirective[0].maxLength as number | undefined
-      const allowedTags = sanitizeDirective[0].allowedTags as
-        | string[]
-        | undefined
+      const maxLength = sanitizeDirective.maxLength as number | undefined
+      const allowedTags = sanitizeDirective.allowedTags as string[] | undefined
+      const pattern = sanitizeDirective.pattern as string | undefined
 
       if (
         fieldConfig.type instanceof GraphQLNonNull &&
         fieldConfig.type.ofType instanceof GraphQLScalarType
       ) {
         fieldConfig.type = new GraphQLNonNull(
-          new SanitizedString(fieldConfig.type.ofType, allowedTags, maxLength)
+          new SanitizedString(
+            fieldConfig.type.ofType,
+            allowedTags,
+            maxLength,
+            pattern
+          )
         )
       } else if (fieldConfig.type instanceof GraphQLScalarType) {
         fieldConfig.type = new SanitizedString(
           fieldConfig.type,
           allowedTags,
-          maxLength
+          maxLength,
+          pattern
         )
       } else {
         // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
diff --git a/packages/api/src/generated/graphql.ts b/packages/api/src/generated/graphql.ts
index d14428b39..d1e733acc 100644
--- a/packages/api/src/generated/graphql.ts
+++ b/packages/api/src/generated/graphql.ts
@@ -2501,6 +2501,7 @@ export type ResolversParentTypes = {
 export type SanitizeDirectiveArgs = {
   allowedTags?: Maybe<Array<Maybe<Scalars['String']>>>;
   maxLength?: Maybe<Scalars['Int']>;
+  pattern?: Maybe<Scalars['String']>;
 };
 
 export type SanitizeDirectiveResolver<Result, Parent, ContextType = ResolverContext, Args = SanitizeDirectiveArgs> = DirectiveResolverFn<Result, Parent, ContextType, Args>;
diff --git a/packages/api/src/generated/schema.graphql b/packages/api/src/generated/schema.graphql
index e3c5630a8..2f77183e1 100644
--- a/packages/api/src/generated/schema.graphql
+++ b/packages/api/src/generated/schema.graphql
@@ -1,4 +1,4 @@
-directive @sanitize(allowedTags: [String], maxLength: Int) on INPUT_FIELD_DEFINITION
+directive @sanitize(allowedTags: [String], maxLength: Int, pattern: String) on INPUT_FIELD_DEFINITION
 
 type ArchiveLinkError {
   errorCodes: [ArchiveLinkErrorCode!]!
diff --git a/packages/api/src/scalars.ts b/packages/api/src/scalars.ts
index 2be928e6e..22404534f 100644
--- a/packages/api/src/scalars.ts
+++ b/packages/api/src/scalars.ts
@@ -8,10 +8,15 @@ export class SanitizedString extends GraphQLScalarType {
   constructor(
     type: GraphQLScalarType,
     allowedTags?: string[],
-    maxLength?: number
+    maxLength?: number,
+    pattern?: string
   ) {
     super({
-      name: `SanitizedString_${allowedTags}_${maxLength}`,
+      // Names must match /^[_a-zA-Z][_a-zA-Z0-9]*$/ as per graphql-js
+      name: `SanitizedString_${allowedTags}_${maxLength}_${pattern}`.replace(
+        /\W/g,
+        ''
+      ),
       description: 'Source string that was sanitized',
 
       serialize(value: string) {
@@ -25,6 +30,9 @@ export class SanitizedString extends GraphQLScalarType {
             `Specified value cannot be longer than ${maxLength} characters`
           )
         }
+        if (pattern && !new RegExp(pattern).test(value)) {
+          throw new Error(`Specified value does not match pattern`)
+        }
         return sanitize(value, { allowedTags: allowedTags || [] })
       },
 
@@ -36,6 +44,9 @@ export class SanitizedString extends GraphQLScalarType {
             `Specified value cannot be longer than ${maxLength} characters`
           )
         }
+        if (pattern && !new RegExp(pattern).test(value)) {
+          throw new Error(`Specified value does not match pattern`)
+        }
         return sanitize(value, { allowedTags: allowedTags || [] })
       },
     })
diff --git a/packages/api/src/schema.ts b/packages/api/src/schema.ts
index 43fa75719..08def9c86 100755
--- a/packages/api/src/schema.ts
+++ b/packages/api/src/schema.ts
@@ -8,6 +8,7 @@ const schema = gql`
   directive @sanitize(
     allowedTags: [String]
     maxLength: Int
+    pattern: String
   ) on INPUT_FIELD_DEFINITION
 
   enum SortOrder {
@@ -1273,7 +1274,7 @@ const schema = gql`
 
   input CreateLabelInput {
     name: String! @sanitize(maxLength: 64)
-    color: String!
+    color: String! @sanitize(pattern: "^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$")
     description: String @sanitize(maxLength: 100)
   }